No matter what I try RPR 2.2.1 seems to be unable to correctly render some normal maps in tangent space (using either Principled BSDF or Uber Shader Node). No issue at all in Cycles & Eevee but RPR render it as if it was in World Space instead of Tangent space. Happens with both OBJ & FBX meshes (FBX stores the tangents so the renderer shouldn't have to mess with them ). See screenshots below. Eevee is perfect while RPR is messed up.