Vetex actually answered a good handful of ppl a long time ago:
Do note that it’s been 5 years since this was stated so things can shift around. Especially considering Freedrock’s fate, and that this was in reference to WoM which was around 1,500-2000 years after the events of AA and want not. But its still an okayish means to get a general gist of how everyone’s going to fare during the time of AO and after it.
Devastated is a massive understatement.
Its safe to assume that anything that existed in those seas, most certainly don’t exist anymore. Especially if DurzAcheron’s last ditch at taking down PK if they were going down caused a chunk of the earth to get launched into space.
But we’ll have to see since AA lore is in an ambiguous state. Don’t even know if Chaos ravaging the 7 seas, more specifically the 4th, 5th, and 7th seas, is cannon still or not.
Edit:
Here’s the full AU lore doc btw:
Its also in-game as the Arcane Chronicles, but its better to have the google doc itself since you don’t have to be in-game to look at it.