I see you can get one on white but does that happen on 2 as well? (with out trading)
Yes, via an ingame trade, that is. Once you have talked to Yancy / Curtis 50 times on the XTranceiver, they will offer random Pokemon up for trade. Ralts is one of those.
Source Source 2
How to change your username How to add a user avatar Why was my post hidden? Question etiquette Flags vs Downvotes Anime FAQ Official PokemonDb League
Type a Pokemon name, type, move or ability to see instant results.