So most people know about how in gen 2, shiny Pokemon are determined by stats, and stats also determined the gender of a Pokemon. Due to this, female Pokemon can't be shiny because they can't have the right stats. Are genderless Pokemon also shiny locked this way, or is it still possible to get shiny genderless Pokemon?
Yes, it is possible to get genderless shinies. The IVs are random and can be any number, therefore they can be the IVs to make it a shiny. If it wasn't legal, it would say it isn't legal.
Source: https://play.pokemonshowdown.com/teambuilder(I tested this with Mewtwo, a genderless Pokemon and I validated it with the right IVs for it to be shiny, and it said it was legal for Gen 2 Ubers)