Questions about the free InfinityBlade Assets - Terrain files specifically

Hi I have a question regarding specifically the asset from the Grassland pack. There is a file in Plains>Env_Plains_Terrain called M_Terrain_Blend. My question is how can I use something like this in a Landscape Blend so I can paint different textures on weight and height layers? Am I able to do that?

I know how to created Landscape Blends from textures but I am wondering if there is a simple way to change this blueprint to enable this?

Also what is the benefit of creating a terrain blend like this? Thanks for you time.