My brother claims he played this hack that was on an app on a Nokia 5220 during 2010 The only things he remembers about it is that it had swears in it, a ball was even called mierda ball and pokemon from other generations were added in.
Are you sure that it was a hack of Pokémon Crystal? Hacks of Pokémon Ruby and Sapphire are by far the most common hacks of Pokémon games. Pokémon Quartz is a hack of Pokémon Ruby that includes some adult humour, but the game uses fake pokémon only.
This kind of reminds me of Pokemon Vietnamese Crystal Version. It also reminds me of how the European Spanish versions of Pokemon games are obscene in Latin America.
But I really think this is just an obscure ROM hack.