Edit, solved (problem was probably some internet browser glitch).
I created character model with rig and animations. I exported FBX from blender, imported it to sketchfab. Animations work, but when i try to add texture maps, everything is black. Same FBX file works perfectly when i import it to Unity. I can add and see all color, normal and metalnes maps. Only here i cant get textures to work. Where is the problem?