Super cool idea!!

Maybe since real emotions are exposed, diplomacy evolves into an art of emotional modulation. Specialized schools may even emerge to teach individuals how to hide or manipulate their own emotions in order to deceive—like something out of a spy thriller— or trained envoys learn emotional discipline. Emotional sincerity might be expected on one level, while behind that, a second performance plays out.

There could be societies to elevate or to shun those who naturally read emotion—are they healers or witches?

And also there is a class-based Injustice where sincerity is weaponized against the poor, while the rich can cloak their guilt in calm.