Unreal is creating a mesh for inserting random textures.
If you look closely at the UV map in the screen shot, the red areas are aligned in addition to the areas.
How do you create a UV like that?
I tried to create a UV like that with a Blender, but I don’t know.
That just looks like a normal UV map to me…
Assuming you have all the edges properly marked, just unwrapping will result in that.
Could you provide more details on the example where it didn’t work?