I'm almost positive it's not possible but i wanted to be sure.
Since $externaltextures saves separate mdl with texture file for optymilization isues it means mdl files can use textures outside of their own file. Maybe there is a trick to use one texture mdl with other mdl files?
ATM im using sub models for variations with one texture but it's a bit inconvenient since i don't see different sub models in Hammer (just body 0).
Or is it posible to see model body variation with cycler?