I think this is normal sometimes, depending on how bright the light is coming from the other direction.
Or it might be a texture issue as I've had the skin textures of NPCs only show up as black for some reason.
Yes i have mods for no more blocky faces,detailed faces, some armor mods and weapon and i had sunglare mod, but i deleted it and its still the same, also when in high places like the throat of the world at night my character is completely dark, anything i can tweak to make it better?