Malkair

Would it be too far out there to propose that Lift might possess some (Siah) Aimian blood? Perhaps being partly Aimian she was able to pass as human, yet retained the ability to ”change” her body, an ability she might not have been entirely able to control? Displaying such an ability in public might have gotten her mother killed, thus prompting her visit to the Nightwatcher, where she asked to have said ability removed. I imagine Aimians being able to change their bodies at will might indicate them having a greater than human presence in the cognitive realm (as has been theorized earlier due to their shadows). Aimians fueling that ability through the conversion of food to stormlight doesn’t seem entirely impossible either. Consequently, Lift’s ability to interact with sprens and metabolize food to stormlight wouldn’t be a direct consequense of the boon granted to her by the Nightwatcher, but rather of her Aimian heritage synergizing with her Nahel bond. I can't say I entirely believe this myself, but at least Lift’s boon literally being the removal of an ability to change does seem to fit her request better than miraculosly gaining other abilities. Judging by the other Aimians we’ve seen it might also explain her somewhat eccentric behavior.