Now the big question: have functioning 3DS flashcards become a reality?
Huh? Gateway's been out a few years now. You need a 3DS with firmware 9.2 or under to run it is the main thing.
Sky3DS is also quite popular now, though I don't know if that one is able to run something like a translation patched game or not (it's more limited in features than the Gateway). I don't believe it's been blocked on post 9.2 firmware (YET!).