Generally speaking, landscape layer blend is about 10x more expensive than re-producing the effect yourself.
Its useful basically only for cinematics and stuff you don’t want to put time into.
Otherwise, take the layer sample, do the math on each of them with subtractions additions etc, and usr it as the alpha to lerp between the different textures you need.
As a byproduct, on top of better performance, you become “immune” to epic’s fallacies.