How can I make 2 separate meshes blend seamlessly while keeping them as separate meshes? I'm trying to make a player model for a video game that can have changeable clothing. So I would have a mesh for the head, torso, legs, feet, and hands. The problem I'm having tho, is that the meshes do not blend seamlessly. There is a very apparent cut where the meshes connect:  How can I make this cut seamless for all the different meshes? Any help is appreciated.
Position all mesh joins under the clothing.

In fact you shouldn't need to "join" the meshes, you position a head and shirt so that the shirt is over the top of the neck vertices.

Another option is to have all clothing and head details in textures, so you always use one solid mesh. Maybe a collection of different complete character meshes with different texture options.