Azula centric ATLA au where everything is the same as canon except around when Azula's 10, Ozai starts to get...nervous.
because a powerhungry domineering heir is all good and well, but also HE was a powerhungry domineering heir. and he 1) eventually super got his dad murdered & 2) would've done it himself way sooner if he was strong enough. and while azula is nowhere near as strong as him *now*, she's a lot stronger than he was at her age and presumably only going to get stronger. keeping her in assassinating distance suddenly seems like a very bad idea.
so he decides he just needs to send her away for a very long time with a somewhat failing mission. keep her out of his way, out of his palace, with a little bit of a smudge on her record so people won't be aligning with her to overthrow him or anything. she's still the preferred heir he just doesn't TRUST her is all!
so he sends her on a mission to...capture the avatar. and she can't come back until she does.
10 year old azula is a lot more politically-minded than zuko was at 14, so she knows this is a wild goose chase he doesn't intend for her to actually succeed at and she is VERY VERY MAD ABOUT IT. she worked so hard to be such a good domineering powerhungry heir for him and hes going to send her away and keep weakling loser zuko around??? unacceptable!!
also iroh definitely stays in the palace to keep zuko safe from plotting and poison so she's just like. alone. her and a crew of sailors who all kind of look down on her, as scary as she is, bc she's 10 and not 14 and on the outs, not the heir (as far as anyone knows).
anyways theres a lot of ways this au could go but ultimately i think the most fun is that she doesn't become like, Good or Anti-War but she also isn't devoted to the fire nation anymore. Instead shes just like "i WILL kill the firelord. don't care what happens after that or around it"
like she joins the gaang and teaches aang firebending, but NOT because she agrees with them. or disagrees with them. shes just like what happens to the world is none of my business what happens to firelord ozai absolutely is
azula: my father thought i wanted to kill him when i was ten years old. i would HATE to disappoint him