A lot of items do share the same models though and are just resized to the needs.
For example : earring seems to at best have 2 models. Else there are moved and resized.
for chest piece it seems to have hyur midlander m, f, roe m, lala m (most of them at least) it is adjusted for the rest of the races. For more difficult attire there is obviously more models but you have the idea.
As the benchmark isn't out I can't tell you if Viera and Rhoth share what piece, or if they reworked them all, obviously. However they did said that all headpieces had to be reworked and that will take time.