It is compatible with landscape brush system. In fact, if you’re using landscape edit layers, the brush system is the only way to get the roads created with the plugin to deform the landscape.
The only issue is that if your landscape is large and you’re using world composition, the brush “explodes” the VRAM usage turning the editor unusable. I’ve experienced that before trying to use the unreal water system plugin (which also uses landscape brushes) to create an infinite ocean on large landscape. It seems to be some sort of memory leak or very unoptimized code on the brushes from Epic’s part.
To sumarize. If you have large landscape with world partition and edit layers, you’ll have a hard time conforming the terrain to the roads. I’m actually still trying to find a way to overcome this without having to manually sculpt the terrain under the roads which will take forever.
edit: I’ve just made a quick test with a clean level. It seems the landscape blueprint brush only works in UE4. In UE5 it has no effect when you click on “update landscape”.