Hi there! I still have this issue in UE4 4.27 version. Was it finally fixed? Has there been a new workaround for this?
I use blender to export the skeletal mesh with a corrective shape key. I check “Tangent Space” and the type of smoothing is set to “face”. In UE4, I have the import normals and tangents checked.
The result is fine in the pose mode, but as soon as the bones move and the corrective shape key is activated, the smoothing groups start to look wrong.
If anyone has a solution, it would be awesome. I have been working on this several days and I found nothing to solve it without duplicating the number of vertices (splitting all the edges), but as the project I’m working on is a mobile VR app, that option is too expensive for me.
for your time!