Well it’s technically a crossover with the Nobunaga’s Ambition series (its Japanese title is even “Pokemon x Nobunaga’s Ambition”). It was also apparently almost a Dynasty Warriors game too…
It’s interesting how Pokemon snap and the ranger series got referenced in Pokemon adventures but Pokemon colosseum and XD never even got any kind of mini arcs like the re-releases for the main series games did.
That’s what Let’s Go Pikachu/Eevee SHOULD have done (maybe have the Surfing Pikachu mini-game too) instead of not even letting you play anything there.