Can we using script to moving the muscles in unity.

if you using the Avatar Settings, you must see the Preview moving muscle, Can we make some script or unity support to do some thing in animation like that or its just the review to set the angle of the bone.

Yes, get the transform of the bone/muscle you want to move and set it’s rotation in LateUpdate().

I posted a question on stackoverflow:

Maybe someone over there can answer this question.