Well, one possibility could be that they team up to fight a common enemy. Maybe a powerful villain has emerged that neither of them can take on alone. They start off not trusting each other fully, Wolverine being the lone wolf type and Captain America used to leading his own team. But as they face challenges together, they learn to respect each other's skills and eventually become great allies.
A plot could involve Wolverine getting caught in a time - travel mishap and ending up in Captain America's era. Captain America is initially suspicious of this strange, feral man. But then they discover that there's a threat to the timeline that only they can stop together. Along the way, Wolverine teaches Captain America some of his more unorthodox fighting techniques, and Captain America shows Wolverine the value of teamwork in a more structured way.
Wolverine's gruff and sometimes anti - social nature might be at odds with Captain America's more patriotic and team - oriented personality. Wolverine might not care much for Captain America's flag - waving ideals at first. But as they spend time together, Wolverine could come to appreciate the values that Captain America stands for. And Captain America could understand Wolverine's more survival - based mindset. They could blend their personalities to form a more effective duo, with Wolverine's tenacity and Captain America's leadership guiding their actions.
One possible plot could be that Captain America and Black Widow are on a mission to retrieve a powerful and dangerous artifact. Along the way, they face numerous enemies and have to rely on each other's skills. Cap's super strength and leadership combined with Black Widow's stealth and combat skills make them a formidable team. They also start to understand each other on a deeper level, sharing stories from their pasts and building a stronger bond as comrades.
One possible plot could be that Naruto, while on one of his travels in search of new jutsu or on a mission, accidentally stumbles into the X - Men's universe. There he meets Wolverine. At first, they might be wary of each other. Naruto could be intrigued by Wolverine's claws and his regenerative ability, while Wolverine might be curious about Naruto's chakra and his ninja skills. They could end up teaming up to fight a common enemy, perhaps a villain who has the ability to disrupt both the ninja world and the mutant world.
In a 'Harry Potter meets Captain America' fanfiction, perhaps they could team up to fight a common enemy. Maybe Voldemort and Hydra form an alliance, and Harry with his magic and Captain America with his super - soldier skills have to combine their forces. For example, Harry could use his invisibility cloak to help Captain America in a stealth mission against the joined forces of the Death Eaters and Hydra agents.
One possible plot could be that Wolverine and Wonder Woman are brought together by a common enemy. Maybe a powerful villain is threatening both the mutant world and Paradise Island. They start off as distrustful of each other due to their very different backgrounds and methods. Wolverine is a rough - around - the - edges mutant used to street - level fighting, while Wonder Woman is a noble Amazon warrior. But as they face the enemy together, they learn to respect each other's skills. Wolverine is impressed by Wonder Woman's strength and grace in battle, and she in turn admires his tenacity and ability to keep going no matter how injured he gets.
The fanfiction could start with Wolverine coming to New York for some personal reasons. There, he crosses paths with Spider - Man. Soon, they discover that a powerful and mysterious figure is causing chaos in the city by mind - controlling both humans and mutants. To stop this threat, they must put aside their differences and use their unique abilities. Spider - Man can use his spider - sense to detect the mind - controlled individuals, while Wolverine can cut through any physical barriers the enemy might create.
In a fanfiction scenario, Nico di Angelo and Captain America could team up. Nico could use his shadow - traveling abilities to get them out of tight spots. Captain America would bring his leadership and combat skills to the table. Their meeting might also lead to some interesting cultural exchanges, as Nico comes from a world of Greek mythology and Captain America from a more modern, American - military background.
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.
Perhaps there's a treasure hunt involved. The pirates believe America has some clue to a great treasure because of his unique position in the world. So they take him along on their adventure, and along the way, there are lots of comical misunderstandings as America tries to explain modern concepts to the pirates.
Friendship is a big theme. Despite their differences, the characters usually end up forming strong bonds. They learn from each other and support one another in facing various challenges. Another theme is the exploration of power. Captain America has his super - soldier abilities, and the Hetalia characters have their own skills and influence. How they combine their powers or deal with differences in power is often a part of the story.