A crossover could start with Wonder Woman being summoned to Asgard by some mysterious magic. She finds herself in a strange new world and is initially met with suspicion. Thor, being the more open - minded of the Asgardians, decides to help her figure out how she got there. Along the way, they discover that an ancient enemy from Thor's past has plans to use Wonder Woman's power to open a portal to a realm full of chaos. They then have to work together to stop this from happening, with Wonder Woman teaching Thor some new combat techniques she learned on Themyscira and Thor showing her the power of the Asgardian magic.
A cool scenario would be a battle royale - style crossover where Wonder Woman is brought into the Marvel universe to participate in a tournament. She has to fight against various Marvel heroes and villains, like Thor and Loki. As she progresses, she discovers that the real mastermind behind the tournament is trying to use the chaos to open a portal to another dimension. Along the way, she forms alliances with some of the Marvel characters and together they try to stop the evil plan.
It might look like a story full of epic battles and cultural clashes. For example, the settings would alternate between the glittering, magic - filled Asgard and the idyllic, yet warrior - like Themyscira. The characters would have to overcome their differences. Wonder Woman, with her grace and Amazonian training, and Thor, with his brute strength and godly powers, would need to find a common ground to fight their common enemies.
A plot could involve a magical rift that transports Thor to Wonder Woman's world. He doesn't understand the ways there at first and causes some chaos. Wonder Woman has to step in to keep the peace and teach him about her world. In the process, they discover a threat that is targeting both their realms and must combine their powers to defeat it. For example, Thor's lightning and Wonder Woman's lasso could be used in a unique way to counter the enemy's magic.
Another possibility is that there is a villain who is stealing technology from Stark Industries (where Spiderman sometimes gets his tech) and ancient artifacts from Wonder Woman's homeland. They are both independently investigating and then cross paths and decide to work together to stop the thief.
One idea could be a story where Wonder Woman tries to rehabilitate Cheetah. Maybe she discovers a way to reverse the effects that turned Cheetah into a villain, and they form an unlikely friendship during the process.
One idea could be a crossover with Superman. Imagine Wonder Woman and Superman teaming up to fight a powerful alien threat that neither could handle alone. Their different powers and personalities would create an interesting dynamic.
One idea could be that Superman and Wonder Woman have to team up to stop an ancient alien threat that is immune to their individual powers. They must combine their strength, speed, and wisdom to find a way to defeat it.
One idea could be that a powerful new villain emerges who is a threat to both Gotham and Themyscira. Batman and Wonder Woman team up to track down the villain's lair. Batman uses his detective skills to analyze the clues while Wonder Woman uses her combat skills in the battles along the way.
Thor's lightning power could be combined with Wonder Woman's bracelets. For example, Thor could channel his lightning through her bracelets, creating a more powerful defensive or offensive weapon. It would be like a super - charged energy blast that could take out powerful enemies.
In a 'Thor meets Wonder Woman' fanfiction, perhaps they meet in a neutral realm. Thor is intrigued by Wonder Woman's connection to the Greek gods while she is curious about his Asgardian heritage. They get involved in a tournament of sorts where they have to team up against other powerful beings. During this time, they share stories of their heroic deeds. Thor tells her about his battles against the Frost Giants and Wonder Woman shares her tales of protecting the world from Ares. By the end of the tournament, they exchange gifts - Thor gives her a small Asgardian charm and she gives him a piece of Amazonian armor.