Specify different templates for row and col titles in FacetGrid.set_titles()

[leo-hstone]

Is your feature request related to a problem?

Using 4-Dimensional Plotting as explained in the user guide one can use set_titles() (docs) using a template. This is applied to both column and row titles.

Describe the solution you'd like

In my example at hand I have different pyhsical quanities for row and cols and would like to add units into the titles. A syntax similar to seaborns set_titles would enable setting different templates for row and columns labels.

Describe alternatives you've considered

Alternative solution by now is to iterate through the axis manually and set the titles.

Additional context

No response

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