I really like the fanfic 'Pepper's Perspective'. This one is interesting because it's told from Pepper's point of view. It gives a deeper understanding of how she feels about Tony, both his genius side and his flaws. It also has some great scenes where she helps him make important decisions regarding Stark Industries.
A good 'Ironman and Pepper Potts Fanfic' should have a strong understanding of their characters. For example, Tony is a complex character, and the fanfic should capture his intelligence, his playboy past, and his growth into a more responsible hero. Pepper is also strong - she's not just a love interest but a capable businesswoman. So, the story should show her in that light as well.
Some fanfictions explore Pepper becoming a superhero herself. Since she's always been around Ironman, she could gain some knowledge or technology that enables her to have powers. This then changes the dynamic of their relationship as they now fight side by side. Another storyline could be about them having a falling out. Maybe due to Tony's overprotectiveness or Pepper feeling like she's in his shadow, and then how they work through those issues to get back together.
In some fanfictions, Tony's personality might be softened more. He could be shown as being more openly affectionate towards Pepper than in the movies. For example, he might constantly write her love letters or surprise her with romantic gestures. Pepper, on the other hand, could be depicted as more assertive in her own right. Instead of just being Tony's support, she could be a force to be reckoned with in business and even in superhero matters.
Pepper Potts is a character in the Iron Man movies and Marvel Comics. She is Tony Stark's (Iron Man) close confidante and later his love interest. She is known for her intelligence, business acumen, and her role in Stark Industries, helping Tony manage his company and often getting involved in his superhero affairs.
In this fanfiction, Pepper might struggle a bit with the idea of being pregnant while Tony is constantly in the spotlight as Iron Man. She could worry about how their child will grow up in such a public environment. However, Tony reassures her that they can create a normal family life within their extraordinary circumstances.
I'm not sure if there is a specific crossover fanfic between Harry Potter and Pepper Potts. It's quite an unusual combination as they belong to different fictional universes. But the world of fanfiction is vast, so it's possible that someone out there has created one.