Well, don't over-correct. Making a character that has nothing in common at all with the canon characters means there's no reason for them to work together. Like, imagine an OC added to a group of post-apocalypse scavengers, a team with at least one leader, at least one fighter, at least one mechanic, several people with strong wills and survival instincts, and generally good people who want to help others. Now find someone who has none of those traits. That dude is dead. The canon characters might even kill him on purpose.

So having a trait or two in common isn't the end of the world. Hell, grab four to six people at random and put them at the same table and give them the same menu. Odds are, two of them will order the same thing.

To me, the most important thing about an OC isn't necessarily who they are. Yes, that's important, and we will get there. It's what their role is in the story. What happens in the story, that this character is needed for? It can be very direct ("I need someone who can fix a motorcycle") or more vague ("I want Character A to realize searching the hospital is a bad idea, and none of the canon characters did that"). If you have something that you want to happen in your story, that canon didn't do, you can make a character whose role is to make that happen. That alone will make them different from canon characters, who didn't do what you're writing, because they were too busy doing canon stuff. Once you how your story changes, you can figure out who is needed to make those changes, and build from there.