Transferring shape keys from a base mesh to clothing/armor

So I have a character basemesh with some corrective shape keys, mainly around the thigh/groin area to help with deformation for sitting poses, and I’d like to be able to use those same shape keys for clothing without having to re-do the shape keys for every different outfit. Is there any way I can sort of transfer the shape keys from the basemesh to the clothing meshes? Or is there a better method not involving shape keys at all?

I’ve been googling like crazy but I can’t find anything helpful on this

I had the same problem recently. I found that the surface deform modifier works in some cases, so you could try that. It gives errors on some meshes though.

Does anyone else know a better way to transfer shape keys to meshes with different vertex counts?

If your trying to transfer a shape key, you can use the join or transfer shape keys feature. I know, I know you have to have the same vertex count. Just make it so. Here is how I do it. First of all, I make sure the clothing area where I want to transfer the shape key has the same topology as the base. Another words the vertices that move are the same. Then I just add a bunch of vertices to the object I want to transfer to such that I can delete them later that are not actual part of the mesh. IE add a cube subdivide it and join it to the mesh like you would two separate objects that are apart until you get the vertex count the same. Now use your transfer shape key from the base to the other object. Finally just delete the vertices of the ones you added to get the vertex count the same and voila, you now just transferred the shape key. I know it is a hack but it works most times. The only catch is that the ones that move should be identical.

In case anyone with the same problem stumbles upon this thread in the future, I did find a solution that fits my needs.

Check out this video here:

The short of it is that you duplicate the base mesh and expand it around the base slightly. Then rig the duplicate to the same skeleton as your base so they move at the same time. After that use the mesh deform modifier on the clothing mesh and set the target as the duplicate. This makes the clothing deform with the duplicate, and since the duplicate has the same vertex count as the base the shape keys can be copied over, thus making the clothing/armor deform with the basemesh, shape keys and all.