In Dance Dance Revolution 5thMIX, 2MB appears similarly to U1 in his case, he has purple hair and wears black sunglasses and his entire appearance is a shadow version of U1.
In DDR HOTTEST PARTY series, 2MB has a human appearance instead of being a shadowy appearance. He is identical to U1's appearance with the same hairstyle and sunglasses and this reveals his hair being dark gray. His sunglasses are neon blue and his main outfit are entirely black as his stomach is exposed from his button shirt. This appearance is actually one of U1's alternate appearance.