HairStudio is not dependant on the skinned mesh. The scalp is simply parented to a bone. So you can create prefabs for your hair styles, and attach these prefab to the head bone of your rig, whetever it is. Note that the hair root implentation is made by painting on a mesh collider. So, if you try and place a hair style on a mesh with a different skull shape, you may have annoying offsets between the hair roots and the skin.