This thread has been a lifesaver for me as I was attempting to get maps from WM to UE for some time. I have since discovered 2 approaches and I am currently weighing the pros and cons of both.
The first one is just taking the inputs from the Unreal Output macro and plugging them into a splatter map converter, then spit that out as a single bmp. Then use that splattermap to height-blend all the layers in the material, using the channels from the map as height inputs.
The second approach is what you illustrated - outputting each height map as a separate file and using those at import as weight maps.
If I’m correct, there’s little benefit in using the former, as it won’t allow me to paint on top of it, right?