Specify group for color and shape in PopulationTimeProfile?

[nina-nauwelaerts]

I am trying to create a population time profile. I have specified 'human plasma' and 'human milk' group to have the observed and simulated data shown in one color for each matrix. In this case, the shapes of the observed data are taken from the dataset names (which are different for plasma and milk from the same individual/reference). I would like to have the plasma and milk observed data from the same reference shown using the same shape. Is it possible to specify one group for color and one group for shape? Or is there another way to obtain such a plot without specifying all the shapes manually?