Plot details about Frozen 3 are still sparse, but the upcoming Disney sequel must give Anna what the previous two movies failed to. The first two Frozen films revolve around sisters Anna and Elsa, showcasing how their individual strengths allow them to overcome any obstacles thrown their way. In the first Frozen, Anna saves Elsa from an assassination attempt, and Elsa saves Anna in return. This sisterly bond is still front and center in Frozen 2, but Elsa gets significantly more screen time to find herself and uncover her powers.
https://screenrant.com/frozen-3-anna-story-previous-movies-failed/