Making two mesh colliders collide

First, I CAN’T use box colliders because I have multiple meshes that are used as the player and making custom box colliders for each would be a pain. But when I use a mesh collider for the player it doesn’t even detect the environment mesh collider (which also can’t be a box collider). In addition, with a box collider for the player it works most times but I’ve found that if I hit a thin object that is part of the mesh in the center of the box it passes through so I can pretty effectively navigate withough touching anything. So how can I make 2 mesh colliders actually collide.

You need to mark the “Convex” checkbox to collide two mesh colliders.
However, as already stated, mesh colliders are computational expensive.

You could raycast along every edge of the mesh.