You uncheck the ‘tangent space normal’ option in the material and then you transform the other normal map using the “transform” node (regular vector, not position) set to tangent-> world. Then you can blend the two normals as worldspace.
You uncheck the ‘tangent space normal’ option in the material and then you transform the other normal map using the “transform” node (regular vector, not position) set to tangent-> world. Then you can blend the two normals as worldspace.