Despite not having access to Switch homebrew, I managed to make a list of all Pokémon in the Rescue Team DX demo with their own IDs. Of course, I can't personally check how accurate it is, but I think it should be fine. As far as a player trying to get custom starters or changing Pokémon in general would be concerned, the order seems to be the same as that of PSMD (which you can find on Project Pokémon). However, near the end of the list, there's data for some story Pokémon. I don't understand the purpose of that, but those are also present in Gates to Infinity (see pic) and likely Super.
As you might imagine, unobtainable/cut Pokémon lack most of their data.
https://pastebin.com/s2704DGf 