"Soulless," Wanda whispered in Wicked's ear, because she could see it. In this form everyone she looked at had a sort of shimmer around them, a light and life, and until now- when she saw the absence of it in her father- she hadn't realized exactly what it was. Now she knew, and it was terrifying. No more terrifying, though, than this pointless massacre. This was what it must be like to be a ghost, pure energy with no outlet, watching, powerless, as the world went on around you. As horror unfolded in front of you.
When her father appeared Wanda felt for her powers, willed them to action, only to realize she had no way to wield them in her astral form. Her instrument, her body, felt so far away and she knew how cumbersome it was. That it would only burn more of her energy to get back and she'd already used up so much just to project her spirit visibly onto this plane for this long. Everything was happening so fast and Pietro was falling and Wanda moved to the edge of the building and saw that Wicked's ghosts caught him.
Wicked's ghosts. This wasn't just what it was like to be a ghost, Wanda was a ghost and maybe Wicked could be her mechanism. Wanda went to her, whispered what she knew, but got no further before Magnus sent out an EMP blast to knock Wicked from her feet. Wanda felt the energy crackle with her own and she shook it off an returned to Wicked's side. "Use me," she demanded. "Use my powers." She didn't know if this would work, if Wicked even knew what she wanted, but they had to try.