If she does come back, I wonder for what action. Since Adam already hinted us on twitter that we will learn what really happened by the end of the season, and thanks to Regina’s Hook’s hint, and that we will see her swan bug in action which might lead to the troll that Rose hinted us, quite possibly she might appear as a ghost (if she was really dead) or might appear in a flashback.
But also tomorrow is the writer’s last day of writing, so I am not sure she would make it or have enough time.