Previously On, the allegorical title to the episode in context with its plot, takes us back on a recap of Wanda's life since the very day when Stark Industries' missile changed her and Sokovia's fate. And in one of those scenarios, the episode may have left us a hint to the origin of her powers. And no, it wasn't the Mind Stone.
Hint At Wanda's Powers
In the episode, Agatha forces Wanda to revisit the day her parents were killed by a missile that struck her house.