The Swan Princess: The Mystery of the Enchanted Kingdom (1998) on Netflix

Plot summary

Zelda helped Rothbart write notes on the Forbidden Arts, and now she wants them back, since they would give her unlimited power. Unable to learn on her own whether the notes still exist, she captures Whizzer, a yakey-bird who can repeat any voice after hearing it once, and threatens him with a fireball that will chase whoever she names. He reaches Swan Lake Castle, where Prince Derek and Princess Odette are preparing for Festival Days. Whizzer learns that Derek found Rothbart's writings and hid them away. Odette, who always believed such material would be burned, urges Derek to dispose of it; he argues that it might one day serve a good purpose. Posing as an accordion slave, Zelda charms Lord Rogers and wins an invitation to stay, though Queen Uberta distrusts her.