The result of turning off Smooth UVs setting and turning it off in the subdivision settings in render package: Maya Arnold (AutoBump Enabled) ↓↓↓ (I mean even autobump feature catches these artifacts) Maya Arnold (AutoBump Disabled) ↓↓↓ Blender viewport ↓↓↓ Artifact seams are still here…
It looks like you have smooth uv checked in the multi map exporter settings.Try turning it off and also turning it off in the subdivision settings in your render package. I'm not familiar with blender, but it could be 'none' or 'linear' maybe? Also worth checking this…