Is it possible to make a mesh plane vertices follow the contour of a landscape in BP?
So when you move the plane the vertices will follow the landscape, like draging a carpet over it.
You need to make that yourself.
First line trace Z coordinates on some grid. When this works, create custom mesh with verticies at those coordinates.
Also there may be one big problem, if you want it to work in editor, all need to be done in constructor script, I am not sure if you can make custom mesh in construction script.
procedural mesh component works in the construction script 