¡Hola Xavi!
Be careful, because I know you already have cool games published in Spanish, and if you are planing to port any of them to English for this Jam, I think it is not allowed.
Rules states that "entries must be previously unreleased", and perhaps this does not applies to the game in other languajes, but as far as i understand for CristopherMerriner's answer to my question in other thread: "But let's say that anyone with previous exposure to your game isn't able to vote on it (and that basically means beta testers, since all games must be previously unreleased). "
If you are talking about translate an already existing new unpublished game in Spanish, that would be a great new! :D