Thank for the help =) For the tests I excluded SP from my workflow and used normal map straight from Marmoset (use it for baking). I double checked all baking settings. That's the results: png 8 bit - Dither png 16 bit- Texture type: Normal psd 32 bit - Texture type: Normal psd 32 bit - Texture type: Default.. What?? And…
Changing the bit in substance painter from 8 to 16 doesn't help a whole lot if it wasn't BAKED at 16bit. Make sure the source stuff you are baking out and importing into painter is also 16bit. Export at 16bit png, or 8bit dithered tga like @Neox mentioned.