O_o all these spoiler tags in a spoiler thread. Well I'm on a phone so I have no choice. Only thing I can't figure out is do we actually know what happened to Hannah? "My sister is gone. And she's never coming back." *creepy smirk*
This thread is listed as having spoilers, so I am fore-going the bar.
From my point of view, Nothing happened to Hannah except most likely the observational world will never consistently see her as Hannah again. Hannnah is there, but it is Eve's job now to interact with the world. Hannah will be there for the baby. Hannah will be there to drive. And Hannah will aways be there to interact with the most important thing/person of her life, Eve.
It will probably be difficult, Simon's body has been 'exposed' and Eve says Hannah did the violence wearing Eve's blonde wig. What a ball of confusion, to borrow from Love and Rockets. And it is designed that way. There will be some case against Eve, she will deal with it. probably some very reduced form of murder or manslaughter, and who knows what sticks.?
BTW, I wonder what name was used in the Glasgow hospital (was Eve still Hannah)? Or if there were records at all. One thing about Eve, she is not the particularly honest one. Her forte was confidence, not fact....