A great fanfiction storyline could be set in an alternate universe where Hulk and Wonder Woman are in a relationship. This would explore how their different personalities and powers interact on a more personal level. For example, how does Wonder Woman deal with Hulk's occasional outbursts? And how does Hulk adapt to Wonder Woman's strong - willed and independent nature? It could be a story full of drama, action, and romance.
One interesting storyline could be where Wonder Woman tries to rehabilitate Cheetah. She might use her wisdom and compassion to understand the root of Cheetah's villainy and attempt to bring out the good in her. For example, she could discover that Cheetah's transformation into a villain was due to a misunderstanding or a wrong done to her in the past.
A great storyline is when a powerful ancient artifact is discovered. This artifact has the potential to destroy the world if misused. Superman and Wonder Woman are both drawn to protect it. However, they face many challenges as various villains also want to get their hands on it. Along the way, they learn more about each other's pasts and how their powers originated, which deepens their friendship and partnership.
Maybe in a fanfiction, they kiss during a moment of extreme danger. For example, Batman is about to sacrifice himself to save Wonder Woman and she stops him with a passionate kiss. This could be the start of a new relationship dynamic where they start to question their previous boundaries and how they feel about each other.
One interesting storyline could be Batman and Wonder Woman teaming up to take on a new, powerful villain that neither could face alone. This villain could be a magical threat that requires Wonder Woman's knowledge of the mystical and Batman's strategic mind.
One interesting storyline could be the two superheroes uniting to fight a new, powerful villain that threatens both Gotham and Themyscira. Their marriage would symbolize the union of two different worlds, and they'd use their combined skills and resources to protect everything they hold dear.
One interesting storyline could be their child having to hide their powers in a normal school. They'd struggle to fit in while also having the responsibility of their superhero heritage. Another could be the child getting kidnapped by a villain who wants to use their unique genetic makeup for evil.
One interesting storyline could be the son's struggle to balance the very different legacies of his parents. He might have Batman's brooding nature and tactical mind, while also having Wonder Woman's sense of justice and connection to the gods. This internal conflict could lead to some great character development.
A great plot could be a love story between them in the fanfiction world. They come from different backgrounds, she's an Amazonian princess and he's a brooding vigilante from Gotham. Their relationship could be filled with misunderstandings at first but then develop into a deep connection. For example, they might initially clash over their different approaches to justice but later find common ground and fall in love.
A more romantic - themed storyline could also be explored. Imagine Iron Man and Wonder Woman falling in love while on a mission together. Their different personalities - Iron Man's cocky and tech - savvy nature and Wonder Woman's noble and powerful presence - would create an interesting dynamic in a relationship. This could also bring in some conflict as they try to balance their duties and their feelings for each other.
A really interesting plot could be that the child is kidnapped by an old enemy of either Wonder Woman or Batman. The kidnapper wants to use the child to get revenge on the heroes. The child then has to use their wits and the powers they've inherited to escape. Along the way, they might make new friends or discover secrets about their parents' pasts that help them in their journey.