Normal map shading in blender 2.8

[helluvamesh]

1. Try flipping the green channel:
   

   
   
   If this doesn’t help, the normalmap doesn’t use Mikk TSpace, which means you can’t use it in Blender.

2. Where did you make/get the normalmap, post a low-res version of it. Does it have anything in the alpha channel? If so, try disabling the alpha channel.