Given the multiverse situation with Pokemon as a whole, they're both the same person and a random stranger that acts as your Battle Subway partner. They aren't related, even in canon. Same for Nate and Rosa, considering the other is just some random kid in the player's eyes standing around outside the train station.
>>46109028I'd say no, not so far. They're either canonically not related at all or the other character just doesn't exist. Next gen would be interesting to see the player character you didn't pick be your little brother/sister, though.
