Rising from Mad Men to The Chilling Adventures of Sabrina, Kiernan Shipka has an interesting spark to her that could lend itself well to Rapunzel. She'd bring a mischievous quality to the role, maybe a bit more outgoing, but still handle herself well. Shipka hasn't shown her singing too much, but she could still make the role work out, and her ability for complex parts is a bonus in Shipka's favor to take on the role.
Going back to ladies with a connection to Disney, Peyton List became famous for her roles in Jessie and the spin-off Bunk'd. Since then, List has become more famous for her lead role in the Netflix series Cobra Kai, which shows off her athleticism. That's a good push for her to play Rapunzel with her moves from bounding off her hair to fight scenes. List can switch from bright humor to sharp drama on a dime, and this would be a great opportunity for her to become a major star.