Unfortunately in this case the topology has to be pretty much identical and skinned exactly the same way as the original faces. It can be done np, but you have to be careful because you will lose the concurrency between the body and the clothing if you reapply an automatic skin-weighting algorithm to either one of them. If there’s a way to directly copy and paste the skin weights onto the clothing from the body, that would be optimal. Each matching vertex needs to be taking on the same exact influences from the bones…down to the .001 to avoid any slip between vert positions that will show passthrough when triangulated edges don’t align.