The Copy Hero

A lot will be changing. Izuku will be born with a quirk. Instant Photographic Reflexes. His personality is Katsuki's while Katsuki's will be Izuku's (Basically they swap personalities). Instant Photographic Reflexes makes it so Izuku can instantly copy any/all movements/actions after observing it performed once, including acrobatics, martial arts, and other physical stunts. With these skills, they can become masters and incredible at what they do, by combining what several forms and movements in rhythmic motions instead of using the same thing over.