FINAL EDIT: @nomad@infosec.pub found it, it’s Roswell Conspiracies, thank you everyone!
The white-haired females would frequently meet at a Stonehenge-like monument where there was also some kind of a portal. I also only remember this one specific scene and nothing beyond that:
(a bit graphic, click to show)
There are men who are restrained, and their mouths are being held open. An elderly man places a large egg on top of a ramp, and the lower end of the ramp is connected to the mouth of one of the restrained men. The egg eventually hatches, and a big snail emerges from it. The snail then slowly slides down the ramp and enters the mouth of the man, who is forced to swallow it. As a result, the man is immediately brainwashed and gains additional physical powers and will serve as an additional soldier for that old man.
EDIT: the art style resembled that of X-Men Evolution
The egg snail brain control thing sound like animorphs but that was live action. I do remember a cult of white haired evil druids but can’t place that
They were indeed like a coven! One of them wasn’t evil though.
Roswell conspiracies?
HELLL YEAAAAAAAAAH
Thanks a lot, that’s the one!