They're not glitches, I think there was one or two in-game trades that can be lower than they are in the file so far, and maybe some that are underlevelled in multiple routes in Gen 2.
I was considering using the Old Man Glitch to see if I could get something like a level 1 Mewtwo ported up to Gen 7 (just for my amusement rather than this site). Any idea of Poke Transfer picks that up as illegal?
We don't have it; it's the rarest underleved ever made actually.
Few informations exist about this event : https://www.serebii.net/black2white2/funfestmission.shtml
I also have the original source somewhere, will search
To be fair, my void-Jubilife Arceus was transported March last year. Maybe they finally upped the checks? (doubt it tho)
It's at Lv 100, Met level 100 (due to transporter), EV untrained, and interestingly it doesn't have Judgment in it's moveset.
@YoshiMoshi These must be all of them if I didn't miss one.
Gen 4: Azure Flute + Infernape (from GameStop Deoxys distribution decchi.bin) Wailord (from Movie 11 Shaymin distribution)
Gen 5 Shiny Litwick + Bulbasaur (from Summer 2011 Shelmet & Karrablast distribution) Pidove (from Secret Eggs distribution)