>>55809867Mainline game, yes, but it's in its own isolated timeline that has no actual influence on the rest of the mainline games.
GameFreak uses a specific "prime timeline" of canon events when writing callbacks or continuations/extensions of previous games, and LGPE clearly isn't on there considering it directly contradicts Johto's events by demoting Red to an irrelevant NPC who was never at any point Kanto's champion, and more importantly, was NOT the kid who dismantled Team Rocket.