It's actually a kinda overused storyline for the base premise -- older sister has strange (i.e. spirit) talents and is sent away at a young age because she's seen as a "jinx" to Spirit Cloud Mountain while younger sister is a pampered, spoiled brat. Hmmm, yes, we can see our Happy Marriage parallels easily, though this one might have come before it. Then the emperor has arranged a marriage between the Grand Councillor's daughter to Prince Ye, but he has a reputation of being cold and heartless and evil Grand Councillor has plans AND younger daughter doesn't want to marry Ye either (until she sees him later and has regrets) so they recall the free spirited older sis and make her go through with the marriage, sort of holding her servants (Auntie Xu (?) and Qu'er) as hostages.
So, at first it's the classic thing where he declares he doesn't want her anywhere near him (while she's hiding under a table, so he doesn't even see what she looks like) and sends her off to a busted up Serenity Palace building. But then she winds up running into him later dressed like a ninja, into one of his brothers who thinks she's a maid (and she shoulder throws him, much to his immediate joy; he crushes on her immediately) and into another brother, who witnesses her taming the untameable horse (Ye's).
Meanwhile, our psychic princess (I have to think that the original Chinese is less goofy than the translation, but maybe not) has a ghost servant and soon adopts another one that's been haunting the Serenity Palace. They are called Mochi and Sesame.
So while he doesn't trust her at first, she continues to intrigue him with her very non-princess-y ways. She knows martial arts, she argues with him all the time, she's not remotely demure, etc. etc. The consorts, including the former favourite, of course detest her. There's political machinations via her father. There are evil Taoist priests who want to steal her away. There are good fairies that become her friends.
I finished season 1 and can't find season 2 (or, strangely enough, the manga/donghua/manhua version) even though there was news that it was supposed to be out in the 2023/2024 season, though in a weird 3d-ish animation style. I can find online translations and supposedly the season 1 of the anime covered up to around Chapter 130 (and there appear to be over 500 chapters). Taking a peek at the online version it has a bit of a different feel / pace than the anime, though the bones are the same.
I guess let me cover this...I did enjoy it, the weirdness notwithstanding. She's a strong character, though the voice actress for her has a particularly whiny, high pitched voice that kind of gets on your nerves -- I know it's supposed to be the "cute" voice but, eh, not to me. The art is actually okay once you get past the weirdness of the opening title song. It's SO weird. I did wind up binging it very quickly, so it held my interest and it's annoying that season 1 ended so abruptly, so I did like it and I am glad I watched it. I'll probably even attempt to read it online as there's no other way that I can find, though the translations are...not the best.
Edit: Ok, I found a reasonably (but not great) translated version online and I've been reading it. Up to Chapter 337 out of 500 something. The anime went to roughly Chapter 125? It is both better and worse than the anime, though some of the "worse" might be due to the somewhat iffy/ridiculous translation. Maybe.
Pro for the anime is that some of it was restructured so that the story makes more sense. And the art is much more consistent.
The most ridiculous things for the written version is that we're supposed to believe that this 20-something year old (or maybe older, it isn't clear) prince with an ACTUAL harem and even a favourite concubine, has NEVER before had sex and has no idea what to do. Nor have any of his brothers, except for the Crown Prince, who is married and a total horn dog.
Then, there's a whole section about how they have a past connection and have been reincarnated (I guess?) where neither one were human. He was the Sage King of the Devil Realm and she was a Sky Fairy (and princess? maybe?). And their romance in that past life was also just about as weird, where she went to the Devil Realm dressed as a man (but not remotely looking like one; I mean, the girl has obvious boobs even when wearing men's clothing) and he figures out she's a woman, sort of...but literally is like asking her "Are you a woman?" like he's never seen one before when he has handmaidens who gush all over him all the time.
Anyway, while I am finding it moderately interesting, it's also got a lot of stuff that makes no sense at all. I am not sure if I'll finish it. I kinda just want a summary. And, seriously, if you could just skip through all of the wrist grabbing and forced kissing and "Shocked" faces, it'd probably take the chapter count down from 500 something to like 200.