https://bulbapedia.bulbagarden.net/wiki/Gender
In Generation II, a Pokémon's gender was determined through its Attack IV. Due to this, a female Pokémon could never have a maximized Attack stat (unless they were a member of an all-female species, such as Smoochum), because female Pokémon were given the lower portion of the IV range. This also prevented female Pokémon of a species with a gender ratio of seven males to one female, such as starter Pokémon or Eevee, from being Shiny, due to that also being based partly on the Attack IV. From Generation III onward, neither of these traits are determined by IVs, allowing for Pokémon species with two genders to have females with maximized Attack and simultaneously retain their chances of being Shiny.
So, Starter Pokémon (Kanto and Johto) Eevees(Evolution:Vaporeon-Sylveon) Fossils(Gen1) Snorlax Togepi(Evolution) can‘t be Shiny when gender female in Gen2 GB and Gen1-2 VC