If we're listing other characters Sakurai might've considered, there's still...more to doubt.
- Blastoise: Was ultimately replaced by Squirtle, has competition with Gen 8 when it comes to Pokemon in general, and Meowth or Eevee if they revisit gen 1
- Toon Zelda/Tetra: We haven't had toon LoZ games in a while, the duo would need to be a whole lot different than she would've been in Brawl, are they ever planning on re-rereleasing the HD releases the Wii U got?
- Plusle & Minun: Ultimately depends on if pra_mai really was meant to be them, and if popularity is why a new Pokemon gets in over gen 8 shilling, they struggle on official polls in comparison to numerous other gen 3 mons and Pikaclones, and speaking of clones Sakurai would need to find a way to make them less like Pikachu if they were meant to be a last-minute clone.
...There is no Tetra. We only have a file name and it says quite clearly Toon Sheik. He wouldn't say an incorrect file name like that for the sake of it. The only thing of Tetra we have is she's on a poll of popular characters he has. There's zero evidence she was ever in the data. Considered? Maybe. However, keep in mind he has created Clone OC's before like Giga Bowser, so it's not like a Toon variation on Sheik is something he wouldn't do. Tetra requires an all new moveset, and only has the model. Toon Sheik has no model, but is very easy to make a moveset for. Don't get me wrong, I think he would've dropped the Toon Sheik concept for Tetra anyway, but as of now? We only know Toon Sheik was planned along with Toon Zelda.
As for the Pokemon, the specific reading of the Japanese letters for every other Pokemon is completely different from how Pra_Mai is, suggesting it's not a Pokemon. However, it's not some silly thing like "Random" either. We just simply don't know. It's a fair guess, but it doesn't match up right with the other ones. The only real notable thing is that the two at least have a Trophy, but unless that Trophy's data matches Pra_Mai, it's not a good point in its favor.