In this micro-course, author Paul Neale teaches methods of building multiple materials using tileable textures that are blended together on a surface using the Vertex Color and Lerp nodes.
https://dev.epicgames.com/community/learning/courses/AJq/unreal-engine-blending-and-tiling-textures
hi,
i am so amazed by your engine, i can´t believe it, it´s just “unreal” 
after spending years with unity 3d, buying amplify shader to make work easier, i am stunned to see you guys have it all out of the box. WOW!
thanks a lot
cheers