Lerp-ed normal maps height difference

Hi, I have 2 normal map textures and I use a lerp and a mask to blend them. I want it to look like as if one of the materials was over the other. So I want to add a small height difference to the edge of where the two textures blend. How do I do this?

bump******

Did you find a way to do this?What I did was combine both normals with a BlendAngleCorrectedNormals node and plugged the result into the A and B inputs of a HeightLerp using my base material height map as the transition phase and a world position Z coordinate as height to indicate the location of transition between the two normals on the mesh.
There’s probably a better way to do it but that seemed to work.
Might be simpler to convert the normals to height maps,Substance Designer can do this or just bake the height,HeightLerp them then convert to normal in Ue4.