There could be a fanfiction where the Dursleys read the books secretly. As they read, they are filled with a sense of dread as they realize how horribly they've treated Harry all these years. This self - realization leads to a series of internal and external changes within the family.
One interesting Dursleys fanfiction could be about Dudley's life after learning the truth about the wizarding world. Maybe he starts to have a change of heart and tries to make amends for how he treated Harry over the years.
Some Harry Potter - themed fan communities on social media platforms might also be a source. For example, on Reddit, there are sub -reddits dedicated to Harry Potter fanfiction. You can post a request there asking for 'Dursleys read the books' fanfictions, and the community might be able to point you in the right direction.
One interesting fanfiction could be about the Dursleys having a change of heart before Harry goes to Hogwarts. Maybe they start to see the magic in him in a different way and struggle with their newfound feelings of protectiveness. It could show a different side of the usually cruel Dursleys.
One popular fanfiction might be about the Dursleys' secret past that somehow ties them to the wizarding world in a more complex way. For example, perhaps there was a wizard in their family line long ago that they've been trying to hide. Another could be a story where the Dursleys have a change of heart much earlier than in the original series and start to embrace Harry's magical nature, leading to all sorts of comical and heartwarming situations as they try to understand the wizarding world. And there could be a fanfiction where the Dursleys are forced to face the consequences of their mistreatment of Harry in a more magical and extreme way, like being haunted by magical apparitions that represent Harry's pain.
There might be a fanfiction where the Dursleys are actually related to a minor wizarding family in some convoluted way. This discovery could lead to a whole new set of adventures and relationships for them. They could be dragged into a wizarding mystery that forces them to cooperate with Harry and other wizards, which would be a huge change from their usual behavior of trying to avoid all things magical.
They would probably be horrified. The Dursleys are very set in their ways and the strange and often unorthodox ideas in fanfiction would be too much for their narrow - mindedness.
One popular one might be 'The Hidden World of Harry' where it delves deep into how Harry copes with the abuse from the Dursleys and his journey to find a place of peace within himself. It shows his internal struggles and how he starts to stand up for himself against the Dursleys' mistreatment.
One popular 'Harry Hates the Dursleys' fanfiction could be 'The Dursley's Worst Nightmare'. In this fic, Harry finally stands up to the Dursleys in a very assertive way. He uses his magic not to harm them but to make them understand how much they've wronged him.
One great fanfiction could be 'A New Beginning'. In it, Harry is taken from the Dursleys in a very unexpected way. Maybe a powerful wizard, seeing the mistreatment, decides to rescue him early. Another could be 'The Escape'. It might focus on Harry's journey after being taken from the Dursleys, how he discovers new magic and new friends outside of the Dursley environment. And there's also 'Harry's New Path' which could explore how Harry's character develops differently without the influence of the Dursleys.
One good one might be 'The Tormented Years' where it delves deep into Harry's emotional turmoil. It shows how his anger grows over the years of abuse from the Dursleys. Another could be 'Harry's Hidden Struggles' which focuses on his internal battles while dealing with the Dursleys' mistreatment. And there's also 'Anger and Resilience' that portrays Harry's journey from being an angry, abused boy to a stronger individual.