I have a number of characters that fall somewhere inbetween "Canon characters from a published series" and "original characters from a setting of the player's creation"

We have a habit of taking series that we like, or that we thought had squandered potential, stripping out all the canon characters while keeping the setting vibes and rules, and repopulating them with our own original characters. Jun here, for example, was from a tabletop RPG campaign we ran that was set in a world remarkably similar to the one the Manwha "Tower of God" takes place in, but contained our own explanations for mysteries that were never answered in the canon version and our own cast of characters who have never heard of any of the canon characters because they don't exist in this world.

Would that be acceptable?