Had this problem since switching to UE5. Tried many things, but nothing helped. But I just came across the flag “Used with Clothing” in the “Usage” category in the material editor of my Outline material (in my memory I had already tried this in 5.3). Now (with 5.4.4) it has fixed the problem in the editor for me. However, I haven’t made a build with this “fix” yet to really validate it. Please let me know if this works for you.
