Lunar: Dragon Song

What do you mean by "is there Genesis and Dragon Song"? The game as released in the US is Dragon Song, and in Europe and Japan is Genesis. There is only one entry in gamefaqs for both of these names. If you are asking why it's called Dragon Song in the US instead of Genesis as in Japan or Europe, that's simply because of marketing, to make the game sound similar to "Lunar: DS". And if you are talking about AR codes, I'm assuming they won't work between different versions since this game was released by different companies in Japan, US and Europe. That means each game is slightly different, which is enough to make any AR code incompatible.