How is the Pokémon League done in fanfics?

I'm pretty new to the fanfiction side of the Pokémon fandom. So far, I haven't really read any for myself (which is something I should probably do, I'll take recs), though I have been writing a "bible" for my own fanfiction that's going to be three parts long. The first part is going to be centered around learning about the MC and how he handles his first Pokémon journey, with the setting of the part being in Sinnoh. Generally a shonen-esque part with a side of lore. Though, because I haven't read anything, how do I go about writing out the way that the Pokémon league is done?

Is it 1 to 1 with the games? Is it similar to how the anime and/or Galar does their leagues? Or is there a completely different way its done?

Apologies for not really "enlightening" myself to begin with.

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u/RetoroKun — 8 days ago
▲ 235 r/pokememes

inspired by an Emerald vs Platinum meme from over a week ago

no I do not wanna hear it about B1W1. Those games walked so their sequels could run.

u/RetoroKun — 11 days ago