One extra thought to offer: When you know that a certain piece of apparel is equipped(assuming the game has some kind of equipment system) you can either apply a vertex weight map to displace the vertices negatively along normals to shrink it or even hide parts of your mode if it is split into multiple appropriate pieces.
One solution requires custom shader, while the other will cause more draw calls because there is effectively multiple models in place of a single one. So pros and cons to both.
