A great plot could be a time - travel adventure. A villain has gone back in time to change key events in history to gain ultimate power. Captain America, being from the past himself, has a unique perspective on how to fix things. Superman, with his super strength and flight, helps them quickly move through different time periods. They face challenges like not changing too much of the timeline themselves and fighting off the villain's minions in various historical settings.
Well, perhaps a plot where they accidentally end up in an alternate dimension. In this dimension, their powers are different. Captain America might have some super - speed and Superman might have a more tactical mind like Cap. They have to figure out how to get back to their own dimension while also dealing with the villains of this new world. They learn from each other's skills and grow closer as friends throughout this adventure.
The Red Skull could be the main villain. He could team up with some other super - villains or get his hands on some kryptonite - like substance. He would try to use his knowledge of Captain America's past and Superman's weakness to defeat them. He wants to rule the world and sees these two heroes as the biggest obstacles in his way.
Well, they might start off as a bit cautious around each other. Captain America could be impressed by Superman's superpowers which are on a whole different level compared to his own enhanced human abilities. They could end up teaming up to fight a common enemy, like an alien invasion or a super - villain who is too powerful for either of them alone.
One idea could be Captain America arriving on Themyscira and being initially met with suspicion by the Amazons. But as they learn of his values of justice and courage, they start to respect him. He could then train with the Amazons, sharing his combat techniques while also learning from their unique fighting styles.
One possibility is that he wakes up and discovers new allies. The story could then revolve around him building relationships with these new characters while still holding onto his old values. He may also have to deal with the fact that the world has moved on without him and find his new place in it.
Well, perhaps Captain America could be on a mission to seek an ancient Asgardian weapon to help in the fight against a new threat on Earth. He might meet Thor and the other Asgardians, and have to prove himself worthy in their eyes, just like he did in his own world.
Well, in a 'Dbz Captain America crossover fanfiction', perhaps there's a threat that endangers both universes. Captain America's sense of justice and unwavering moral compass could inspire the Z - Fighters. They could learn from his strategic thinking. And Captain America could be amazed by the power of ki and the Saiyans' transformations. Maybe they start training together, with Captain America trying to keep up with the intense training of the Z - Fighters, and in the end, they save both universes.
One possible plot could be that a new super - villain emerges who has the ability to manipulate time and space. This villain starts causing chaos in both Gotham City and the world where Captain America operates. Batman uses his detective skills to try and figure out the villain's plan, while Captain America rallies the superheroes in his world. Eventually, they cross paths and team up. Captain America's leadership and combat skills combined with Batman's intelligence and gadgets prove to be a formidable force against the villain.
One possible plot could be that Captain America is in a situation where he accidentally injures a fan during a chaotic battle. Maybe he's fighting a powerful enemy in a crowded area and his shield goes astray. He then feels extremely guilty and tries to make amends by using his resources to help the injured fan recover. He might also face public backlash for the incident which adds to his internal struggle.
The Night King could be a great antagonist. His army of the dead and his own powerful magic would pose a huge threat to Captain America. Cap's used to fighting human foes, but the Night King is something entirely different.
He could also meet Odin. Odin might view Captain America as an interesting mortal from Midgard and might have some words of wisdom or a task for him to complete during his stay in Asgard.