That's equal to piracy and the original developer of that game can have that copied 'version' taking down. I like games that are unique and not concocted lazy works. That said I don't know of any similar game to FF.because you know, some video games just copy the other one, and changes a little to make it new games, but the fact is, they just copy what the other games has.
Yes, actually there are a lot of RPGs out there, but one that you could check out is called- The Last Story and it looks quite interesting,-also what's cool about this game,it was directed and co-written by Hironobu Sakaguchi, the original creator of Final Fantasy. This game was just going to be released only in Japan,but later went stateside-and the music sounds great also!