I'm also on a Brandon Sanderson kick (for roughly two years now). I'm currently reading The Sunlit Man. It's good, but don't read it until you finish the Stormlight Archive series and the standalone novella Shadows for Silence in the Forests of Hell. Most of the Cosmere stories are fairly approachable in isolation, but this one is very dense with references to established characters, places, and lore, to the point where it should be considered a sequel or spinoff. Even I feel a little lost!
If anyone's looking for an easy way into Sanderson's Cosmere (it's intimidating! I get it!), I highly recommend the novella The Emperor's Soul. It's self-contained, it's short, and it's just a fantastic story. If you prefer listening to reading, Graphic Audio has an "audio movie" version which is a nice taste of what they offer, too.
@dresden@discuss.online let me know if you want recommendations on reading order before you continue on to The Lost Metal.