build parsing errors for locales - Cannot augment module 'xxxx' with value exports because it resolves to a non-module entity

[carmiele]

Environment:
Angular - v8.xx.xx
Node - 10.14.1
Typescript - 3.5.3
TSLint - v5.20.1
Webpack - 4.39.2

I am getting ton of build errors whenever I try to build my Angular application with any imports from date-fns and am trying to figure out why. Using and running the application after the build shows that the imports work perfectly, and I can use the functions after in the application. It's just my compiler/linter that seems to be complaining. I do have a bunch of older versions for my environment for compatibility reasons, so not sure if one or a few or these are the issue/s, or if it's an issue with the configurations I have set for the build.

Also, are there typings I can possibly import/need to import to resolve these issues?

Here is my code:

import { Locale } from 'date-fns';
import { es, zhCN } from 'date-fns/locale';
 ...
  ngOnInit() {
    this.localeImport = zhCN; 
    // proceeds to use this in another object...
...
 }

And my tsconfig settings:

"compilerOptions": {
    "importHelpers": true,
    "outDir": "./dist/out-tsc",
    "sourceMap": true,
    "declaration": false,
    "module": "commonjs",
    "moduleResolution": "node",
    "noUnusedLocals": true,
    "noUnusedParameters": true,
    "emitDecoratorMetadata": true,
    "experimentalDecorators": true,
    "allowSyntheticDefaultImports": true,
    "target": "es2015",
    "typeRoots": [
      "node_modules/@types"
    ],
    "lib": [
      "es2018",
      "dom"
    ],
    "baseUrl": "./"
  },

There are the errors I am getting:

node_modules/date-fns/typings.d.ts(12359,9): error TS2649: Cannot augment module 'lastDayOfWeekWithOptions' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12369,9): error TS2649: Cannot augment module 'lastDayOfYear' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12372,9): error TS2649: Cannot augment module 'lightFormat' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12375,9): error TS2649: Cannot augment module 'max' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12378,9): error TS2649: Cannot augment module 'min' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12381,9): error TS2649: Cannot augment module 'parse' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12384,9): error TS2649: Cannot augment module 'parseISO' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12387,9): error TS2649: Cannot augment module 'parseISOWithOptions' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12396,9): error TS2649: Cannot augment module 'parseJSON' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12399,9): error TS2649: Cannot augment module 'parseWithOptions' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12414,9): error TS2649: Cannot augment module 'roundToNearestMinutes' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12417,9): error TS2649: Cannot augment module 'roundToNearestMinutesWithOptions' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12426,9): error TS2649: Cannot augment module 'set' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12441,9): error TS2649: Cannot augment module 'setDate' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12444,9): error TS2649: Cannot augment module 'setDay' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12447,9): error TS2649: Cannot augment module 'setDayOfYear' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12450,9): error TS2649: Cannot augment module 'setDayWithOptions' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12461,9): error TS2649: Cannot augment module 'setHours' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12464,9): error TS2649: Cannot augment module 'setISODay' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12467,9): error TS2649: Cannot augment module 'setISOWeek' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12470,9): error TS2649: Cannot augment module 'setISOWeekYear' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12473,9): error TS2649: Cannot augment module 'setMilliseconds' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12476,9): error TS2649: Cannot augment module 'setMinutes' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12479,9): error TS2649: Cannot augment module 'setMonth' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12482,9): error TS2649: Cannot augment module 'setQuarter' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12485,9): error TS2649: Cannot augment module 'setSeconds' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12488,9): error TS2649: Cannot augment module 'setWeek' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12491,9): error TS2649: Cannot augment module 'setWeekWithOptions' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12503,9): error TS2649: Cannot augment module 'setWeekYear' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12506,9): error TS2649: Cannot augment module 'setWeekYearWithOptions' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12518,9): error TS2649: Cannot augment module 'setYear' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12521,9): error TS2649: Cannot augment module 'startOfDay' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12524,9): error TS2649: Cannot augment module 'startOfDecade' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12527,9): error TS2649: Cannot augment module 'startOfHour' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12530,9): error TS2649: Cannot augment module 'startOfISOWeek' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12533,9): error TS2649: Cannot augment module 'startOfISOWeekYear' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12536,9): error TS2649: Cannot augment module 'startOfMinute' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12539,9): error TS2649: Cannot augment module 'startOfMonth' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12542,9): error TS2649: Cannot augment module 'startOfQuarter' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12545,9): error TS2649: Cannot augment module 'startOfSecond' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12548,9): error TS2649: Cannot augment module 'startOfWeek' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12551,9): error TS2649: Cannot augment module 'startOfWeekWithOptions' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12561,9): error TS2649: Cannot augment module 'startOfWeekYear' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12564,9): error TS2649: Cannot augment module 'startOfWeekYearWithOptions' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12575,9): error TS2649: Cannot augment module 'startOfYear' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12581,9): error TS2649: Cannot augment module 'subBusinessDays' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12584,9): error TS2649: Cannot augment module 'subDays' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12587,9): error TS2649: Cannot augment module 'subHours' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12590,9): error TS2649: Cannot augment module 'subISOWeekYears' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12593,9): error TS2649: Cannot augment module 'subMilliseconds' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12596,9): error TS2649: Cannot augment module 'subMinutes' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12599,9): error TS2649: Cannot augment module 'subMonths' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12602,9): error TS2649: Cannot augment module 'subQuarters' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12605,9): error TS2649: Cannot augment module 'subSeconds' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12608,9): error TS2649: Cannot augment module 'subWeeks' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12611,9): error TS2649: Cannot augment module 'subYears' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(12614,9): error TS2649: Cannot augment module 'toDate' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(15685,9): error TS2649: Cannot augment module 'af' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(15688,9): error TS2649: Cannot augment module 'ar' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(15691,9): error TS2649: Cannot augment module 'arDZ' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(15697,9): error TS2649: Cannot augment module 'arSA' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(15703,9): error TS2649: Cannot augment module 'be' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(15706,9): error TS2649: Cannot augment module 'bg' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(15709,9): error TS2649: Cannot augment module 'bn' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(15712,9): error TS2649: Cannot augment module 'ca' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(15715,9): error TS2649: Cannot augment module 'cs' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(15718,9): error TS2649: Cannot augment module 'cy' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(15721,9): error TS2649: Cannot augment module 'da' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(15724,9): error TS2649: Cannot augment module 'de' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(15727,9): error TS2649: Cannot augment module 'el' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(15730,9): error TS2649: Cannot augment module 'enAU' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(15733,9): error TS2649: Cannot augment module 'enCA' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(15736,9): error TS2649: Cannot augment module 'enGB' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(15742,9): error TS2649: Cannot augment module 'enUS' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(15745,9): error TS2649: Cannot augment module 'eo' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(15748,9): error TS2649: Cannot augment module 'es' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(15751,9): error TS2649: Cannot augment module 'et' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(15757,9): error TS2649: Cannot augment module 'faIR' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(15760,9): error TS2649: Cannot augment module 'fi' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(15763,9): error TS2649: Cannot augment module 'fil' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(15766,9): error TS2649: Cannot augment module 'fr' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.d.ts(15769,9): error TS2649: Cannot augment module 'frCA' with value exports because it resolves to a non-module entity.
    node_modules/date-fns/typings.