In my opinion, if Scott Pilgrim's world has magical elements, he could be one in theory capable of changing his appearance, the protagonist could try to change his appearance to one more in line with his personality and his powers and abilities, my suggestion would be to obtain the appearance or at least the abilities of John Constantine, a human specialized in mystical and demonic arts capable of making Lucifer himself owe him favors, preventing Hell from having his soul, and being immortal due to the war that could cause his death in all hell, a genius in manipulation and strategy etc etc, is that not only does he have powers similar to Matthew Patel, but even the way they both dress is similar