Looking to graduate from YA Fantasy to Adult Fantasy, what’s a good starting point?

Hello, long time reader here. I am looking for a new fantasy series to keep me engaged for a little bit.

I’m in my early twenties so I definitely feel an itch to “upgrade” to adult fantasy, what’s a series you’d recommend for this?

I’ve heard a lot about Brandon Sanderson and I’m contemplating starting with him. Which of his series would you recommend I start with?

From the YA World, I fell in love with the Shadowhunter series by Cassandra Clare, of course Harry Potter, The Hunger Games, some of Sarah J Mass’ works, Percy Jackson.

I love immersive world-building as much as the next person but what attracts me most is character. I’m a lover of good dialogue, complex relationships that change as the story progresses. I love a good quest/adventure. I gravitate a lot toward books that have poignancy. Sorry if this isn’t enough to preface my taste. I’ve been a reader my whole life and I still feel like I haven’t scratched the surface of literature. I’m really hoping to expand.