In a recently published AL-Legal module contained within Pipyap's Guide to All the Nine Hells (available on the Dungeon Masters Guild), there is a "Bloody Fervor" effect (minor spoilers below):
For every hour spent inside the Gorge, a creature must make a DC 25 Wisdom saving throw. If they fail, they must attack the nearest creature in the Gorge that succeeded on the saving throw. The effect only ends when the creature leaves the Gorge for more than one hour.
The calm emotions spell (PHB, p. 221) states:
You attempt to suppress strong emotions in a group of people. Each humanoid in a 20-foot-radius sphere centered on a point you choose within range must make a Charisma saving throw; a creature can choose to fail this saving throw if it wishes. If a creature fails its saving throw, choose one of the following two effects.
Alternatively, you can make a target indifferent about creatures of your choice that it is hostile toward. This indifference ends if the target is attacked or harmed by a spell or if it witnesses any of its friends being harmed. When the spell ends, the creature becomes hostile again, unless the DM rules otherwise.
Let's say Fred the Fighter & Clarence the Cleric both spend an hour in the Gorge while staying close together. Fred then fails his Bloody Fervor saving throw, while Clarence succeeds it, thus making Fred compelled to attack Clarence. Assuming that leaving the Gorge is not an option, could Clarence cast Calm Emotions on Fred, choosing the second effect (quoted above) to prematurely end Fred's Bloody Fervor?
This is within the scope of Adventurers League play, where GMs must follow the rules more (and I'm asking as the GM).