Just saw this today!!!
Kattriella-san, Jasmine actually did wear pale indigo/lt violet/lilac twice in the film----during the wedding announcement in her main princess dress, just before Jafar turned into a snake; and again at the very end when she and Aladdin reprised 'A Whole New World' while Genie said 'Made ya look!' just before the credits.
It's her 'royal' color and main princess gown theme. (The aqua turquoise 2 pc she wore is her 'casual' outfit and not her 'ball gown'---much like Briar Rose's peasant outfit is what she wore most of the film but of course, her changing princess gown is what everyone knows. Same with Cinderella and Belle.
They wore their 'casual/peasant/maid' outfits for the majority of their film, but their main color and dress is their fancy schmancy ones they wore for 2 minutes, that most all the merchandise follows.
I myself actually am very happy each gal has their own theme color! 15 princesses with 15 different theme colors! Yay for variety!
Tam I Am-san, the Moana head is her Little Kingdom head, but enlarged because she and Elena's LK dolls are too small! Wonder why Hasbro did that? The other 13 princesses are all mix n' match and the same scale/size.
But the Elena and Moana 'matching' dolls are too tiny! So I redid them to match in scale the other gals.