I haven't read his books, but I'de be thrilled to see some serious game made in that univesre. Now, it is more likely that Amazon will make show out of them (as Sanderson was involved with Wheel of Time), but given how terible Amazon's Wheel of Time is (and it seems this will be faith of Rings of Power as well), I'm not too optimisitc about it.
Funny thing is, ASOIAF never got any big budget game either - I'd love to see open world RPG set in Essos and eastern parts of that world, ultimately with you ending up in Shadow Lands and Stygai.
But most of all I would love to see game based on Elric of Melnibone, who influenced so many fantasy authors and doesn't get enough appreciation these days. There is a game being developed at the moment scheduled for 2024, but it seems to be smaller budget project, so I hope they will be able to pull it off.