Her controlling personality would make her critical. She'd be looking for any deviation from what she considers the 'correct' version of the story.
Umbridge is a very traditional and authoritarian character. When reading Harry Potter fanfiction, her personality would lead her to be extremely judgmental. She would be appalled by any fan - created stories that go against the established order in the original books. For example, if a fanfiction showed Harry as being friends with Death Eaters in a positive way, she would be horrified. Also, any fanfiction that promotes ideas of equality between different magical creatures in a more radical way than in the original might be seen as a threat by her. Her narrow - mindedness would prevent her from enjoying or even tolerating most of the fanfiction out there.
Given her self - righteous nature, she'd likely condemn fanfiction that portrays characters in a different light or adds new, unapproved elements to the wizarding world.
Another idea is a time - travel fanfiction. Harry goes back in time and has to deal with Umbridge when she was a student. He tries to change her path so that she doesn't become the horrible person she is in his time. This could involve him befriending her and showing her the value of kindness and freedom.
There's also a fanfic called 'Umbridge Unmasked'. This one shows a different side of Umbridge. Instead of just being a one - dimensional villain, it explores her insecurities and how they drive her actions. It's an interesting take on her character that makes you think more about her role in the wizarding world.
She would probably be outraged. Umbridge is a strict and rather narrow - minded character in the original series. Fanfiction often takes creative liberties that she would likely see as subverting the 'proper' order of the wizarding world she thinks she upholds.
It could start with Harry being forced to work with Umbridge on a special project at Hogwarts. At first, they're at odds, but as they work together, they gradually find common ground. For example, they might both be interested in a particular area of magic that is relevant to the project.
A common plot in 'Harry Potter Dolores Umbridge Fanfiction' is her getting a taste of her own medicine. For example, in some stories, she is put through the same strict and cruel rules she imposes on others. It's a satisfying plot for those who dislike her character in the original books.
She'd be appalled. Umbridge is all about following the rules and maintaining the status quo. Fanfiction doesn't adhere to the official canon she so firmly believes in.
She might view the power dynamics in the fanfiction differently. Given her own experiences with power struggles in 'The Hunger Games', she could be more critical of how power is used or abused in the Harry Potter fanfiction world.
Batman's brooding and serious personality would likely make Harry more cautious. Batman is all about planning and preparation, and Harry would pick up on that. For example, Harry might start to analyze magical situations more thoroughly before acting, instead of just relying on his instincts.
Deadpool's irreverent personality would likely make Harry less uptight. Harry has always been under a lot of pressure, but Deadpool's carefree and often inappropriate humor could make Harry see the lighter side of things more often.
One interesting non - smut fanfiction could be about Dolores Umbridge facing a moral dilemma. Maybe she has to choose between following the Ministry's strict orders blindly or doing what she believes is right for the students, which is a very different take from smut - related stories. Also, there could be fanfictions where she is the main character in a mystery at Hogwarts, trying to solve a problem that has nothing to do with adult or inappropriate themes.