we don’t get any problems with taa with our settings. Default settings are bit too soft but i just changed them and its work perfectly.
r.temporalaasamples=4
r.temporalaacurrentframeweight=0.1
we also use normal curvature to roughness and baked normal map variance to roughness texture(composite texture). On mobile we use msaa4. What settings you are using and can you provide some video/screenshots.