I mean Agatha...
In her origin, she defends herself against the rest of her coven, who are trying to execute her. Her crime was basically not knowing her place, and the people she kills are witches, so she doesn't come across as particularly evil.
In the present, she enters Wanda's fantasy, helps her to understand where her powers come from, and confronts her about her wrongdoing. She offers to allow Wanda to continue living in her fake world peacefully if she'll hand over her power. She doesn't seem to have any kind of Big Evil Plan for what she'll do with the power, which Wanda is already abusing anyway. I don't think she ever actually hurts anybody in the present (other than Sparky?). She kidnaps Wanda's imaginary kids, who Wanda later destroys anyway, and she mind-controls substitute Pietro, who doesn't seem all that disturbed compared to Wanda's victims. She seems to be written in a stupidly hostile and abrasive way just so that we'll understand that she's "bad" and one gets the feeling that if she'd just asked Wanda nicely she'd have cooperated in the first place.
Agatha's POV is actually closer to a traditional superhero plot: picture a hero who infiltrates the villain's fantasy world, makes her understand what she's doing is wrong, takes her power away to prevent her from harming anyone else, but leaves her to happily live in her fantasy after freeing the innocent civilians. That's like a Superman story.
Instead our "hero" Wanda ignores Agatha's pleas for mercy and condemns her to perpetual suffering, telling her she'll come back for her if she needs her help to become even more powerful (note: Wanda is already more powerful than the evil overlord who wiped out half the universe, and the other heroes of this story were helpless to stop her from doing whatever she wanted). They don't seem to be driving at any kind of moral ambiguity: the protagonist being upset justifies the means. There is something telling about the way the civvies act aggressively towards Wanda after being freed, instead of being terrified of her. Are they that stupid? The plot wants to treat her as an ostracized victim despite it making no sense at all. She mind-raped all of them and her penance is to get stared-at in a mean way.
