So there’s a petition on change.org with over 30K signatures for Princess Leia to be inducted as the first “live action” Disney princess.
Since Disney purchased Star Wars productions a some years back, it’s possible.
Personally, I would like to see it happen. She does fit the criteria to be a princess. She is Padme’s daughter, who was once Queen of Naboo. If you argue that her adoptive parents aren’t loyalty, Senator Bail Organa was never mentioned as royalty, but his mother was royalty.