DC : The Template System

A teenager from Earth is transmigrated into a chaotic world of heroes, villains, and cosmic forces far beyond his understanding. Waking up in a strange body with no identity, no records, and no safety net, he is forced to claw his way up from the shadows. His only advantage? A Template System—starting with none other than Madara Uchiha. By day, he lives as Max Martinez, a quiet mailman in Star City. By night, he becomes Tobi, a masked menace feared by criminals and pursued by heroes. Every fight, every kill, every close call inches him closer to full synchronization but the question is what will he do with that power. — Description from novelcodex.org