What gets to her? Spinning, 3D motion, etc?
The whole of Seuss Landing should be good, all 3 water rides, Dr Doom's Fearfall, Kong, Hogwarts train, Flight of the Hippogriff, motionless seats at Minions, I'm sure others I've forgotten.
Hulk/RRR are also likely fine, depending on how sensitive she is. Also Gringotts and Mummy. And ironically Kang and Kodos Twirl & Hurl is just essentially Dumbo, so no motion sickness worries.
Typically Forbidden Journey and Simpsons are worst for most people. My friend can't handle spinning and MiB was worst for her.
If your mom likes to ride, also consider the trans-derm scop motion sickness patch, to allow her to forget her sickness worries and just enjoy everything.