i don't know much about face paints, so i don't know if the design is taken directly from an indigenous group or just trying to emulate it. it is at the very least in poor taste i think.
also to those attempting to defend it by saying that the concept is inspired by the film princess mononoke, i'd be more inclined to believe that and rescind the criticism if the design looked like the one that san wears in the film but it's not even the same color nor a similar design.