If Harry Potter were raised by John Wick in fanfiction, it would be a very different story. John Wick is a no - nonsense kind of guy. He'd instill a sense of discipline in Harry that might not be the same as what he got from the Dursleys or Hogwarts. Harry would probably be more street - smart. For example, he might not be as naive when it comes to dealing with dark wizards. Also, John Wick's knowledge of weapons and combat could give Harry an edge in fighting the Death Eaters, even if magic is his main weapon.
In a fanfiction where Harry Potter is raised by John Wick, the whole dynamic of the story would change drastically. John Wick's world is full of danger and survival. He would raise Harry with a different set of values. Harry would be more attuned to the idea of protecting himself and others at all costs. His approach to magic might also be different. Instead of relying solely on spells, he could combine his magic with John Wick - style combat techniques. This could make him a formidable opponent against Voldemort. He might also be more secretive and less likely to trust others easily, having been raised by someone as guarded as John Wick.
Well, Harry would probably be an even more badass wizard. John Wick is known for his combat skills and survival instincts. He'd likely train Harry in self - defense from a very young age, so Harry might be more physically capable in the wizarding world. Maybe he'd use some of John Wick's moves in duels at Hogwarts.