I know there is a chance it will never happen but I fear they may choose to kill off Y'shtola with her final moments being performing her Sorceress LB "Aetherial Wind" to defeat a enemy using the last of her life energy or just have a instance in 5.3 where we play as her and use her LB at the end to show the full potential of her powers now she is unleashing everything learned as a Sorceress trained by Master Matoya.

Y'shtola's Sorceress Job LB called "Aetherial Wind" is this as first revealed in Final Fantasy Brave Exvius...
https://www.youtube.com/watch?v=ct8MBG_LEAk