I intend to have my setting on Earth and the elven world of Orlas. Is this something that's interesting? The story will be a fantasy/si-fi mix. While on Earth there are a world with guns and stuff, there's conflicts on Orlas with the elves who uses bow and swords. However the wars are connected and you know, lots of different stuff happen. Would this be something that's interesting?
Something interesting is a relative way of asking this question. Have you ever read a movie or book synopsis that made you think it will be good/bad and ended up being good/bad? Like, I read the synopsis for Game of Thrones when I was 14 and I put the book down on the shelf. I began reading the book years later and found out that the story was beyond interesting and I cannot STOP thinking about the world of the seven kingdoms. Factually, I've read handful of books with a multi-world setting that were both good and bad. If you want to see if your setting is interesting you have to give us details about what's going on because just telling us a flat out X and Y doesn't lead us anywhere.
If it is well written with good characters and a believable plot, then it will be interesting. As a setting, I believe what you have described has the ability to support characters and plots that could be interesting if handled well. Whether or not the setting is interesting to you is a more important question. You are the one who will spend months or years writing about it.
@LegendsTheFour do you really think anyone on this forum would have guts to tell you that your setting idea sucks?
@LegendsTheFour well, no... but maybe you could ask some more practical questions: an idea may sound ludicrous, but still be a basis for a good story... So: what's tg he story 'bout?
Its almost impossible based on a setting or even a synopsis to determine whether a story will be good. There are so many aspects. The setting is fine, but it's just a setting. It's the characters and the writing and the pacing and the everything that will make a good read. If you like the setting and it kindles the fires of your imagination, then just start writing. Have fun. Don't worry about what people will think of your setting so much. Just write.