Reminds me that Jessica Drew is also involved with Wundagore, I wonder if the reason she isn't dead is because she wasn't born there, or because she lacks a twin, 'cause maybe that place only kills twins lol.
Anyways, High Evolutionary said he just sent the kids back to their parents in Uncanny Avengers, and quite clearly says Marya is the mother:
(Uncanny Avengers#4 vol 2)
But then Wanda and Pietro now are the children of Natalya:
(Scarlet Witch#4 vol 2)
So yeah, for a while there was a possibility that Wanda and Pietro were Ana and Mateo, but then that was undone with the reveal that Natalya is the mother.
So, Wanda has four potential mothers, all of them just happened to have twins too, and to make it funnier, of those four mothers, two of them are partially the explanation of her powers, Natalya by being a previous Scarlet Witch, and Magda by being a gypsy:
(Vision and Scarlet Witch#5 vol 2)
Although that one could be Samhaim bullshitting her lol.
Still, it's weird so many reveals about Wanda happen in second volumes, two of them even happen in a fourth issue, almost sounds like an intentional joke from Marvel lol.
Edit:
Ah, yeah, going by definitions like that, then they can't be called mutantions, but even if Marvel cared about that kind of accuracy, not calling characters like Polaris and Rachel "mutants" just wouldn't look as cool lol.
But I can understand wanting some details to be done in a specific way, in my case, there's the clones situation, even if I'm willing to accept clones inheriting the original's memory, I find it ridiculous when they also just happen to be just as competent in combat for example, when stuff like that is muscle memory, and a newborn body just shouldn't have muscle memory from the original, that's something ya gotta relearn lol.