She has bulging eyes and reminds Elayne of a fish.
Shana is relatively weak in the One Power. Her level of strength is described by "The Wheel of Time Companion" as 37(25) which is a quite low level in Aes Sedai hierarchy.
She is part of the group that is sent to where the Cleansing of saidin occurred, because they are expert at reading residues. Some time after they report that they found a large hole where Shadar Logoth used to be.