https://forum.square-enix.com/ffxiv/threads/530946-Evercold-THANK-YOU-for-not-spoiling-it-like-Dawntrailmy reply in response to this topic:
1.The Winterer's specifically the man on the fourth shard as hinted at by Caelix
2.They want to rejoin the fourth shard with the source to prevent their world from collapsing an slipping away from Eitherys an will go to any lengths to accomplish said goal
3.not too hard too guess since we know this expansion will be based on norse mythology concepts so likely we will be fighting trials consisting of norse gods an or titans
4.they've revealed some dungeon bosses and stated the giants from the trailers will be boss encounters
5.its pretty heavily implied by the trailer that the main protagonist the Last Azem title barer can use his magic to bring people with him to other shards using his key which responds directly to the shards of Azem's aether
6.they've mentioned the girl with the bird's name an the roegydn fella with the shields but we don't know who the old woman or child is, an as you said the one eyed Au Ra could be Odin but instead of using that name they might use Odin's real name an then there's the girl who turns to ice we don't know her yet
7.considering most the locations are just floating ships we can probably conclude the final zone will be on the surface of the 4th shard's world which is said to be a frozen wasteland so we can likely expect areas similar to coerthas or ilsebard to appear in the final zone
8.yes correct the airships are the main central areas but they are more like floating cities to be fair an its likely we may not get any other new areas outside that unless they do something unique for like beast tribes or do another cosmic exploring like thing an have us explore more parts of the surface of the fourth etc
9.this is just my speculation but given that OC and PT were poorly received upon launch they may skip this type of content an just try something else an cosmic exploration is mixed reviewed some like it but others are bored by it an were not expecting it to be so one note an on the nose so they may change this up as well.
outside of that they've already confirmed "business as usual" type content an they've added a new gold saucer area though didn't say if it was a permanent addition or just limited to the collaboration event similar to all the fall guys area works but we will see. they've confirmed changes to how chocobo will work stating that you will even be able to summon them as dungeon campanions an similiarly trusts will be changed alongside that so that you can party with your friends an fill missing roles with an npc controlled character to improve the flow of gameplay an make queing times lessened, they are also implementing a universal chat and party finder/duty finder so that you can match with all data centers on your region which will help people clear content consistently and ofc character creation and customization of clothes will be seeing some big changes too.
