Tony would probably be more reserved and less flamboyant. Peggy is a very composed and serious person, so her influence might make Tony tone down his more ostentatious tendencies.
Tony may develop a darker side. The allure of the Infinity Stones' power could corrupt him. He might start to make decisions that are not in the best interest of the world but rather for his own gain or to satisfy his newfound thirst for power. This would create a lot of conflict, both within himself and with his friends, and add a whole new dimension to the fanfiction.
Steve being Tony's godfather could have a huge impact on Tony's life. Steve's old - fashioned values would contrast with Tony's more modern and sometimes self - centered ways. This could lead to many conflicts at first, but gradually Tony would start to understand and adopt some of Steve's values, making him a more well - rounded person.
Natasha may come to view Tony as a kindred spirit. If she discovers that he also has a longing for real connection like she does, she'll feel a sense of kinship. His true nature might show that he is not as different from her as she initially thought. They could then develop a closer friendship or even something more, as they realize they share common emotional ground beneath their outward appearances.
Well, it could start with Percy being in awe of his famous uncle. Maybe Tony initially sees Percy as just another young relative but as time goes on, he realizes Percy has a unique set of skills or a great mind. They might start working on projects together in Tony's high - tech lab, gradually building a closer bond like a mentor - mentee relationship that evolves into a more equal partnership over time.