Categories do have parallel structures in other languages than English. The same category in different languages are then coupled with aka-template. The people in these coupled categories will be visible the other coupled categories.
For example, the Dutch language category Rotterdam, Zuid-Holland, Nederland and the English language category Rotterdam, The Netherlands are coupled with the aka-template. Therefore it doesn't matter whether you put [[Category: Rotterdam, Zuid-Holland, Nederland]] or [[Category: Rotterdam, The Netherlands]] on a profile. The profile will appear in both categories.
However it seems some Dutch language categories weren't made in this way. They were made to represent a category for the Netherlands.