Yeah, I doubt Y'shtola would die. She's the FFXIV character in crossover/none canon games such as Theatrythm. And with Dissidia coming to the PS4, where she is a playable character, I doubt they would remove her from the game.

I'm still salty about Ysayle's death, so I'm a bit more pessimistic and wouldn't be surprised if they kill Y'shtola.