There is a mouse smoothing option that’s i think in the gameplay settings. Turning that off helped me with motion sickness. Also make sure you have a high refreshrate monitor with adaptive sync and try to keep those fps high. For me once it goes below 90 it tends to get bad for me but above that i’m fine. I don’t see/notice a big difference between for example 60 and 90 (60 still seems fine to me) but my stomach disagrees.

Make sure it’s in AHCI mode and not RAID. It’s probably a setting under storage, at least on newer ones it is.