Anisoptera

Insect Plague. Anisoptera summons hordes of dragonflies all creatures within 30ft of Anisoptera take 10 damage. 

Legendary Resistance (3/Day). If Anisoptera failed a save she can choose to succeed instead. 

Regeneration. Anisoptera regains 20 HP at the start of her turn. 

Shapechange. Anisoptera can transform into a swarm of dragonflies or back into her normal form as a bonus action.  

Innate Spellcasting. Anisoptera can innatley cast the following spells. Its spellcasting ability is Wisdom (spell save DC 19, +11 to hit with spell attacks).

At Will: Misty step, Pass without a trace, Counterspell

3/Day: Commune with Nature, Rary's Telepathic Bond, Otto's Irresistible Dance

1/Day: Conjure Fey, Abi-Dalzim's Horrid Wilting 

Multiattack. Anisoptera can make two Dagger attacks or two Fey Energy attacks.

Dagger. Melee Weapon Attack: +10 to hit, reach 5ft., one target. Hit: 8 (1d4 + 6) piercing damage and implants dragonfly eggs (See Growth Spurt)

Fey Energy. RangedWeapon Attack: +10 to hit, range 90ft., one target. Hit: 20 (4d10) radiant damage.

Fey-bending Hex (Recharge 6). All creatures in a 30ft cone must make a DC 19 Charisma save or take 5d8 psychic damage and become deafened and stunned till Anisoptera's next turn. 

Anisoptera can take 3 Legendary Actions, choosing from the options below. Only one legendary action can be used at a time, and only at the end of another creature's turn. Spent legendary Actions are regained at the start of each turn. 

Move. Anisoptera moves her fly speed without invoking attacks of opportunities.

Attack. Anisoptera can make an attack. 

Growth Spurt (Cost 2 Actions). Any dragonfly eggs including those inside a creature hatch and grow to full size. The target must make a DC 22 Constitution save or take 10d10 piercing damage and spawn a swarm of dragonflies in their space.