Direct and Harsh:
* Vicious crone(s)
* Malevolent witches
* Malicious hags
* Venomous harridans
* Spiteful crones
More Figurative:
* Foul hags (evokes a sense of disgust and decay)
* Hateful she-devils (emphasizes their evil nature)
* Bile-spewing witches (implies bitterness and poison)
* Scourge of the earth (exaggerates their negative impact)
Adding Context:
You could also use descriptive phrases like:
* The spiteful old women who lived in the abandoned house.
* The hags who cackled with delight at the town's misfortune.
* Those venomous crones who poisoned the well.
Ultimately, the best way to describe "spiteful hags" depends on the specific tone and image you want to create.