Weird Material Shading in 8.1.0

[RodFdez]

I have a couple of these types of shading, like a smoothing issue but I'm pretty sure that the surfaces are well smoothed, what could be the problem? Also not an overlapped geometry problem

[GeoffroySC]

Hi,

I understand the issue with the first image. I'm not sure about the second one. 

Could you check your mesh normals?  Do you have overlapping vertices? 

What kind of project is it? UDIMs or Single Tile?

Thank you,

Kind Regards,

Geoffroy SC