One idea could be Natasha going back in time to prevent a major event that led to the loss of many lives. For example, she could stop a certain villain from getting a powerful weapon in the past. This would create a whole new timeline and she would have to deal with the consequences of changing history.
One idea could be a story where Tony and Natasha have to go undercover as a couple on a mission. They start to develop real feelings during the process. For example, they might have to attend a high - society event and deal with all the pretenses while also trying to uncover a hidden enemy. Another plot could be set in a post - apocalyptic world where they are two of the few survivors and have to rely on each other completely to stay alive and rebuild society. Or perhaps a story where they both get trapped in a virtual reality world created by an enemy and have to find a way out together while also facing their own inner demons.
One idea could be that Natasha is on a mission in the wizarding world. Maybe she's tracking down a dark wizard who has some sort of connection to a powerful and dangerous Muggle weapon. Harry Potter could help her navigate the magical aspects of the case, like dealing with spells and magical creatures.
Another idea is that Peter gets lost in a dangerous part of the city and Natasha has to find him. Along the way, she discovers his unique abilities and how they can be used in different ways. She then starts training him to be more in control of his powers while also protecting him from the threats in that area.
Well, a great plot could be that Peter discovers his true mother is Natasha Romanoff after some mysterious events. This revelation could lead him to explore his mother's side of the family and the world of the Black Widow. Maybe he uncovers some secrets that Natasha was hiding from the Avengers, which could put him in a difficult situation with his superhero friends. He would have to decide whether to keep the secrets or expose them for the greater good.
Perhaps a story where Percy and Natasha are both sent back in time to ancient Greece. There, they have to work together to change a certain event in history. Along the way, Percy gets to show Natasha his world of demigods and she gets to use her spy skills in a very different setting.
Another storyline could involve Natasha exploring her past in more depth during the time travel. She could interact with her younger self, giving advice or just sharing experiences. This could lead to a whole new level of character development for her. For instance, she might help her younger self become a better spy earlier on, which would then have a butterfly effect on the future events in the MCU timeline.
One idea could be that they discover they are siblings during a big battle. Maybe they both have a similar power or technology that leads them to figure it out. For example, they find out they have the same kind of energy source in their suits or weapons that was passed down from their parents. Another plot could involve them working together to uncover the secrets of their family's past. They might travel to different places, like an old family mansion or a secret research facility their parents were involved in.
Another idea is that Percy gets thrown into the Marvel universe and Natasha is the first one to find him. She initially thinks he's some kind of new super - powered threat but soon realizes he's from a different realm. They then have to figure out how to get Percy back home while also dealing with the various threats that are attracted to Percy's presence in the Marvel universe.
One interesting storyline could be them teaming up on a top - secret mission. They have different skillsets, Natasha with her combat and espionage skills, and Tony Dinozzo with his investigative and street - smart abilities. Their interactions during the mission, like initial clashes due to different working styles and then gradually growing to respect each other, can make for a great plot. Maybe they discover a conspiracy that reaches far beyond what they initially thought, and they have to rely on each other to expose it.
One idea could be a story where Bruce and Natasha are on a mission together in a remote location. They have to rely on each other's skills to survive. Bruce uses his scientific knowledge to figure out a way to stop a dangerous experiment gone wrong while Natasha uses her combat skills to protect them from the threats around. Their relationship gradually deepens as they face challenges side by side.