Wanda wasn't the villain of this series. If you watched it and came to that conclusion, you watched it incorrectly. Hayward was a villain. He wanted to kill a grieving woman who was unconsciously acting out in her highly traumatic past,
and her innocent family, because he wanted a super-bot that could give him whatever he wanted. Agatha Harkness was a villain. She was exploiting and gaslighting a grieving woman for her own selfish desire to have Wanda's power, and was willing to kill Wanda and her family in order to get what she wanted.
In this show, the real villains are the ones that want to harm/exploit Wanda. Wanda did mess up and caused a lot of trauma in her own grief, however, she did not try to or mean to do what she did. She doesn't need anyone else to try and force more punishments onto her for her actions, she has already received them. She lost her family. She gave up everything she ever wanted in exchange for the wellbeing of everyone she was imprisoning in the Hex. It doesn't matter that her family was created by her, they were real. They were conscious, independent entities that could feel all the emotions that any normal person could. They were real, and chose to give up their lives in exchange for the freedom of the people of Westview. That was heroic. What Wanda chose to do was heroic.
Furthermore, there really isn't anyone with the power to punish her, and trying to punish her for her actions would likely result in dire consequences for the rest of the world. That is not to say what she did was okay. It wasn't. She knows that, and doesn't need to have a "lesson" forced upon her. She knows what she did was wrong, forced herself into isolation in order to discover herself (in a way) and protect others from her powers, and based on what we saw in the show, she is not going to repeat the same mistake again.
As
@Umbran said upthread, the justice system is intended to stop bad behavior from being repeated. Wanda won't repeat her bad behavior. She stopped the person that was trying to take control of her power and intentionally use it to do even more harm than Wanda did. As far as we know, no one else in the current MCU has the power to do what she did, so trying to "set an example" by punishing her would do no good (and as I mentioned above, it would likely do much more harm).
I'm certain some other superheroes are going to try and seek out Wanda. The most likely one (and probably the most qualified one) seems to be Doctor Strange, as we know that Wanda will appear in some capacity in Doctor Strange in the Multiverse of Madness. He could become a sort of mentor to her, helping her control her powers and make sure she doesn't do something drastic with her powers, like, you know, destroy the world.
