Basically regarding the Solus Project. Is there a material for share anywhere or in a current Unreal 4 Marketplace map that uses ground mesh planes and deals with seams by fading them out…somehow!!
Here: The Solus Project: Level & Content | 01 | Project Spotlight | Unreal Engine - YouTube
19:30----to—20:30
There are a lot of ways to sort of blend / fade between meshes - like using a transparent material. However the example your pointing to - the Solus ground planes he isn’t really fading the seams out - what is happening is he has a material that uses world space coordinates for the ground texture instead of UV coordinates. This means the texture is always applied the same to the meshes, no mater how you move or rotate them the texture stays the same size in the same place relative to the world, so when you have multiple mesh pieces that have a seam there is no texture seam because the texture is applied based on the world coordinates so it seamlessly goes across the meshes.
Try it for yourself it’s kind of hard to explain I think. Here is how to do it: