Hm. Her memories are fine in my timeline, and she's still able to speak to me. On occasion, possess me too, though that's something we've negotiated not to happen anymore.

[Not unless Byleth's sense of self suddenly imploded and she was left as the only one at the steering wheel, then she could have his body for all he cared. Dismissing all worries about divine bodysnatching, however, he tugged one of the cakes towards him - the chocolate overload one - and began to plan his approach. It looked like it'd be messy to eat...]

But here, she hasn't said a word. I think she must be asleep, rather than completely absent, as I still have access to her temporal powers. [He took the plunge, carefully using the side of his fork to cut a small piece of the chocolate cake, just large enough for a mouthful.] Albeit very weakened.