Like she said episodes ago, she thinks that Wanda understands that she's an ally, which is how she was able to pass through the wall so easily that first time.
For this instance, the Hex is stronger due to Wanda changing it a few episodes back, but by that point, Monica's dna had already been altered, so she was strong enough to resist the resistance of the Hex, and still pass through, because Wanda still knows subconsciously that Monica is a friend.
Agatha has been causing grief, but she didn't create the Hex. That's still Wanda, so I think Monica was confident/trusting Wanda's innate goodness, that she'd be able to pass through the Hex and survive.
I didn't necessarily view Monica entering the Hex again as reckless. I viewed it as her standing by her convictions (that Wanda isn't evil, and is worth saving), and was willing to take a dangerous risk entering the Hex like she did, because, well, that's what heroes do: set aside risk to themselves to protect others. Her plan was to talk Wanda down, using their similar struggles with grief. If successful, she would, A) save Wanda's life, and B) Save the people of Westview trapped in this scenario Wanda created against her will. It's no different than what most superheroes do in these stories.
I love Monica, and I was so jazzed when her powers manifested. It's time for some Spectrum! So excited for next week's episode.
Now that the Agatha reveal is done, I think it's safe to confidently speculate on whether or not Pietro is from the FOX universe. Agatha could have easily been mind controlling him to play his role and keep Wanda off balance. He doesn't even have to be Mephisto masquerading as Pietro now. All of his out of character moments could be Agatha's doing.
I was on team "not actually Quicksilver" (but I also didn't think he was Mephisto either). Now, I'm thinking he may, indeed, be FOX Quicksilver pulled from his morality, and mind scrambled and controlled by Agnes.
