>>58460603Delta Episode explicitly tells us there are countless parallel worlds with minor differences.
You have one where Red picks Charmander, one where Red is late and gets a wild Pikachu, one where Hikari is named Akari. Infinite worlds, some with big deviations some with small deviations.
In two of those worlds, the Sinnoh champion goes back in time and falls from the sky. They are different from Dawn and Lucas, just like Platinum Dawn and Lucas are different. Or how in some worlds, Lucas and Dawn live reversed lives as trainer and assistant.
Naming your rival Dicks doesn't make him wholly distinct from Blue. They're two instances of the same character, in two parallel worlds. This is text, this is canon.