I don't know which genre my novel is. I'm guessing scifantasy romance (if that exist) My novel contains: - the concept of reincarnation - Gods and Goddesses who live as humans with special powers - Aliens and Shiftshapers living as humans - Magic - Exorcism - Religion - Politics - A love story, the reincarnated man is trying to save his soulmate - Devil worshipping
Fantasy, in my opinion. Whether it crosses into Romance depends on whether the romance plot is the primary plot or not.
The central idea is that a politician who is a King in a past life with special powers tries to save an unknown woman who is his soulmate. She was a Queen in a past life and also has special powers but doesn't know how to use them. The govt is trying to stop the two from getting together and preparing for an alien takeover. All the while, the man and woman fall in love supernaturally.
Okay, definitely doesn't sound like science fiction. That's about all I can say, though. I'm not sure how stories that blend science fiction and fantasy elements are categorized by publishers. If it were me, I'd have to stick with speculative fictions because to me, that includes anything and everything that isn't a normal part of everyday life. But that's me.
It's definitely speculative fiction, to my mind, but that includes both science fiction and fantasy (and horror) if defined broadly. To narrow it from there I think you have to say this one is fantasy.
For example, here's the Wikipedia definition of speculative fiction: "Speculative fiction is a broad literary genre encompassing any fiction with supernatural, fantastical, or futuristic elements, notably science fiction, fantasy and horror." That's always been my understanding as well. When you're dealing with the kind of supernatural elements the OP is talking about, I think you can rule out science fiction. The way in which those elements are present doesn't constitute horror, in my view. So that leaves Fantasy.
I had no idea horror was included. No wonder most so-called science fiction films these days are really horror set in the future/space.
I would say fantasy / Supernatural in my opinion. You describe aliens, gods, and reincarnation, in another light gods could be seen as aliens, or aliens as supernatural beings. Technology alone would not change it into sci-fi. Sci-fi relates to the future tense. 2408 or post apocalyptic in a world where technology has broken down but time has moved forward. Science fiction also greatly revolves around space travel and technology at its core. Similarly, you could say any technology, sufficiently advanced, is indistinguishable from magic (or in this case gods). - Clarke's Third law. This would suggest you could call it sci-fi. However I personally would lean on it being fantasy as it seems like you do not intend technology to be a huge part of the universe you wish to create. Just my two cents.