Quote Originally Posted by Ultimatecalibur View Post
Alma's costume was part of the 13 new model sets created for the Ivalance Raids. It is actually a recolor of her namesake's outfit from FFT (that coloration gets used in several cutscenes).

As other have pointed out Y'sthola is one of FFXIV's representative characters (Zenos being the villain representative) in things like Dissidia. Y'shtola's new Sorceress outfit (and Zenos' upcoming Court Attire) was likely developed in part thanks to Dissidia's dev resources.
I still don't get why they made a unique one for her, she did very little in the story and not one for Ramza. Still not sure why that means Y'shtola was the only one to get a unique outfit and why she's not a black mage with the black mage AF like Uraianger and Thancred