Unfortunately, Wuk Lmao is going to continue being herself for the entire patch cycle as well. The only current "hint" we seem to have about what is to come is that we're not done with Sphene just yet given her "crown" still seems to be active.
Given Dawntrail really is just "FF14's greatest hits collection the WoL went through", now staring Wuk Lamat, I'm just going to shoot my cringe shot, here and now, high in the sky and wait for it to hit me in a year or two when I am wrong and we get something nowhere close to it.
Sphene comes back, but due to the erasure in the final trial, along with her memories being forced back as a result of the interaction with Wuk, her "memories" become corrupted. All the pain and sorrow and loss that she tried so hard to make everyone else forget now completely warps her original directive of why she was created. and essentially becomes Meteion 2.0, deciding that in order to truly "save" her people from the pain and sorrow of loss and death; EVERYONE must vanish. She then finds a way to reactivate Living Memory, and reverses the memory process of Everkeep, now transferring the memories of loss and sorrow and sadness, along with all the memories of the dead, that she took from everyone back to the people who currently have the regulators, making everyone remember the things she tried to "save them from" for the past several decades/centuries. As a result, all of the Alexandrians fears about death and the countless losses over all these centuries come flooding out, a "Final Days" experience for them. Given this is the FF9 reference expansion, I'm going to say that as a result of these emotions going haywire, they will give rise to a "primal" of sorts, aka, Necron, and he'll be our 7.4/7.5 trial as he becomes the physical manifestation of centuries of Alexandria's fear of death and loss, given his lore from said game and how he comes about anyway. Of course, us and Wuk do our best to strike him down but it isn't going well given there are centuries of memories full of loss and despair and fear fueling Necron. But just when it seems all is lost, another Sphene appears, the REAL Sphene's soul this time. She uplifts Wuk to get her to keep fighting for the peace and hope of both their kingdoms, and decides that her final act as Queen will be to give the Alexandrian's a new hope on life and fight with Wuk to protect her people. Wuk and Sphene fuse together, pulling a WoL and Ardbert, as it's revealed Sphene is one of Wuk's reflection shards, and now with newfound power, we beat Necron.
There is my prediction for the patch story, locking it in, for better or for worse.