When I export in engine Creator, and directly use them to coform, only the body can work.
If you export fbx from the file from Creator, then import them back, nothing can work.
Seems the body mesh is splited by UV, so the vertex can’t be right, and my transfer vertex order always crashed on my metahuman test.
Besides, all meshes are triangled mesh.
Best way I found is use a get the source file from Bridge or web Creator. Usually, it’s a maya file.
By the way, strongly suggest that Unreal can offer an officially free download base mesh with source file.
In the maya file, you will get a full body with head, and a body no head, but no head only mesh, and no eyes and teeth in it.
I’m much familiar with 3ds max, so I send to Max for further edit. Keep skin, or collapse it, don’t delete. Use the full body mesh, select the body part by UV, directly delete body mesh to get head mesh.
Now you get perfect head and body. Export FBX, import back to UE, all work good.
Then you can wrap the mesh to your customized one, remember better to keep the pose, and stick vertex by vertex on the open border.
You still need eyes and teeth. I get them from JonCG’s example project on his patron. Fortunately, quadify the mesh won’t break them.
Finally I set in ‘only mesh’ when conform body, and set ‘none’ and uncheck ‘adapt neck’ for head conform.