One idea could be that they are on a secret mission together. The Winter Soldier's past memories start to resurface during the mission, and Black Widow helps him deal with the confusion and the emotional turmoil. They gradually develop a deeper connection as they rely on each other's skills.
A plot could revolve around Black Widow and Winter Soldier having to protect a young mutant who has the power to expose a global conspiracy. Their different skills and experiences would come into play as they face various threats. In this fanfiction, they might also develop a deeper understanding of each other's traumas along the way.
One interesting fanfiction could be about their secret missions together before the events of the main movies. They might have to infiltrate a high - security enemy base where they rely on each other's unique skills. The Winter Soldier's combat expertise and the Black Widow's espionage skills would make for a great combination.
One great 'Winter Soldier Black Widow' fanfiction is 'The Unspoken Bond'. It delves deep into their shared history and the unspoken connection between them. The story is full of action and emotional moments that really bring their relationship to life.
Another theme is trust. Given their backgrounds and the fact that they've been manipulated in the past, their relationship in fanfiction often involves a slow - building trust. They have to learn to rely on each other in various dangerous situations.
One idea could be a crossover with the X - Men. The Winter Soldier could be sent on a mission to retrieve a mutant who has some sort of power that could be dangerous in the wrong hands. He then has to face off against some of the X - Men who are protecting the mutant. Another plot could involve a crossover with Doctor Strange. Maybe the Winter Soldier gets caught in a magical spell that makes him relive some of his past traumas in a different way, and Strange has to help him break free. A third plot could be a crossover with the Guardians of the Galaxy. The Winter Soldier is somehow transported to space and has to team up with the Guardians to get back to Earth while also dealing with some intergalactic threats.
Another interesting plot could be centered around a new threat that specifically targets Sam and Bucky because of their connection to Captain America. This threat could be a powerful and mysterious organization that has been observing them from the shadows. The story could focus on how they uncover the motives of this organization and fight back.
One idea could be that the Winter Soldier has to face his past selves in a dreamscape created by a new enemy. Another could be a story where he teams up with a young mutant who can see his hidden memories and they go on a journey to uncover the truth about his pre - Winter Soldier life. And a third could be a story where he tries to adapt to a normal life in a small town but his past keeps coming back to haunt him.
One idea could be a story where Falcon and Winter Soldier have to team up with an unexpected ally from their past. Maybe an old enemy who has a change of heart and holds the key to stopping a new threat.
One popular trope is the 'partners in danger' where they face various threats together. For example, in many fanfictions, they are on a mission against a powerful new enemy that the Avengers haven't encountered before. Another is the 'slow - burn romance' trope. Since both characters have complex pasts and are a bit guarded, a slow - developing relationship between them can be very engaging. It might start with just a mutual respect for each other's skills and gradually turn into something deeper as they understand each other better.
Their shared history in the Marvel universe also plays a big part. They have both been part of the same dangerous world of espionage and super - powers. Fanfiction allows writers to expand on their untold stories and the moments that might have happened between them but weren't shown in the movies.