That will be good to have the possibilty to create a texture from more than one image per channel. I means, add some imperfection in a second normal map that overlay the first. Also add some irregular pattern in a large texture mapping by overlaying images. A kind of photoshop layer system.
and blending like in UE → How to Paint Blend Materials in Unreal Engine 5 with Megascans landscape - YouTube
Thank you for you advice!
+1 for both (layer and blending)
thx 
It’s quite surprising that after two years of development, the D5 material editor still feels so basic. I’m struggling to figure out how to create multilayer or blended materials—the kind I can easily build in 3ds Max with any of the available renderers.