I don’t know if i understood the question correctly but If this is something that you want to achieve then here is the actor i created and the source that jump started me.
https://www.youtube.com/watch?v=kJyWSzfwEk8 the video i saw when i was looking into splines. I needed to be able to create a path but not with mesh. Hope this helps.
P.S Rotate the spline actor -90 at Y and assign your decal. The actor is a bit of a patch work but it works.