Mental Dominion
The coven reaches into the minds of H creatures it can see within 60 feet. Each makes a Wisdom saving throw against your spell save DC. On a failure it takes (H + half your level)d4 psychic damage and is Charmed by the coven for 1 hour; on a success it takes half damage and is not Charmed. While Charmed it obeys simple commands such as "protect us" or "attack them", and it repeats the saving throw at the end of each of its turns, ending the condition on a success. If the damage would drop a target to 0 hit points, you may instead leave it on 1.
Charmed: the creature cannot attack the charmer or target it with harmful abilities, and the charmer has advantage on social checks against it.
If a charmed creature is damaged by the hags or their allies it becomes Frightened instead and flees. It takes 1d10 necrotic damage at the start of each of its turns for as long as it is Charmed or Frightened. It repeats the Wisdom saving throw at the end of each of its turns, ending both conditions on a success.
MASS HYSTERIA. As a lair action at initiative 20, every Charmed or Frightened enemy cries out. Each creature within 30 feet of one of them makes a Wisdom saving throw against your spell save DC or is Frightened, repeating the saving throw at the end of each of its turns to end it. A creature Frightened this way takes 1d10 psychic damage at the start of each of its turns.