Multiattack. The annis makes one Bite attack and two Claw attacks.
Bite. Melee Weapon Attack: +8 to hit, reach 5 ft., one target. Hit: 15 (3d6 + 5) piercing damage.
Claw. Melee Weapon Attack: +8 to hit, reach 5 ft., one target. Hit: 15 (3d6 + 5) slashing damage.
Crushing Hug. Melee Weapon Attack: +8 to hit, reach 5 ft., one target. Hit: 36 (9d6 + 5) bludgeoning damage, and the target is grappled (escape DC 15) if it is a Large or smaller creature. Until the grapple ends, the target takes 36 (9d6 + 5) bludgeoning damage at the start of each of the hag's turns. The hag can't make attacks while grappling a creature in this way.
Spellcasting. The hag casts one of the following spells, using Charisma as the spellcasting ability (spell save DC 13):
3/day each: disguise self (including the form of a Medium Humanoid), fog cloud