i think that appealing to popularity really works here more.
I have seen no first form pokemon matches in the past month or so, yet i've seen a few full evolution matches in the past week. Not to mention that it looks dumb af. I mean you look at the current list of poke profiles and it looks cool with all the dragons and psychics and other pokemon who are fully evolved, but if we make them named after their first forms we're gonna be looking like some baby verse with all the cutesy little animals.
That feels like prioritizing public reception, which shouldn't be much of a factor in 'verse building, over accuracy.
Also, in theory you could have the 'verse page images direct to the profile, with any name of the line going there, but showing the base form's tabber first, if you're that concerned about the 'verse page's presentation.
People will know we're not exclusively listing the base forms when they click the profile & see all the higher forms are there, too, & redirects can make it doable to search Pokemon by multiple names.
Still....
I believe this is how it should work.
If the pokemon has multiple evolutions then it should be called after the pre-evo
If the pokemon has one line then it is the last evo since it is the last evo that gains the main transformations most of the time.
If such a stance is considered valid, then I'm in support of it, even if it's a bit of a compromise.
Also digimon lists full forms and not first forms
IIRC, Digimon are a bit different, because any Digimon can Digivolve to or from any other Digimon species, or at least a lot, & thus, have an absurd quantity of base & final forms, so they focus on the line related to specific, powerful, notable Digimon.
Most Pokemon do not have such an excess of base & final forms, Dynamax, Gigantamax & Megas aside. With only 1 base form, Pokemon can be a lot more consistent about where a line starts.
Meanwhile, many profiles like Son Goku show the base form first.
& another, albeit, less reputable 'mons-focused 'verse, Puzzles & Dragons also lists base form first for its monsters:
https://vsbattles.fandom.com/wiki/Puzzle_and_Dragons
I think it's weird to disregard Pokedex order, evolution, etc. & arguably, precedent, because of concerns about popular opinion & power of the 'verse.
Still, I feel that I can understand this perspective, even if I don't consider it ideal.