So this is the best RVT blending method I've worked with to date. I made this a while ago & then a Unreal Presentation with the Talos 2 team showed they had something similar so I updated mine to also have their non-smooth blend as an option.
RVT blending Function for Landscapes. Global is Global layers Or Extra Distance blending. RVT for RVT. I added a Normal Blend version for non RVT Blending. This works for all Landscape Materials that have blends.
The Distance Blend Material Function is just the same one from UE but with the Clamp updated to a Saturate (optional - not required).
If you want to use with Brushify you replace what is inside the "MF_Landscape Camera" (Don't delete the old shader, move it off to the side).
You can use the Brushify outputs Macro/Global & throw them in here to use the automatic switches.
If you don't like automatic switches you can copy the RVT switch from inside MF_RVT_Landscape (Brushify) & place it here without the auto RVT switches to manually turn RVT & RVT Blending off/on.