A Batman x Atwoman fanfic could also focus on the emotional side of their relationship. Imagine Atwoman has a personal vendetta against a particular villain. Batman initially doesn't understand why she is so obsessed. But as he gets to know her story, he realizes that it's similar to his own quest for justice. This understanding brings them closer. They start to share their feelings and fears, and this newfound emotional bond helps them become even stronger allies when facing the challenges in their cities, whether it's fighting gangs or stopping mad scientists.
A Batman x Atwoman fanfic could also be set in an alternate universe. In this universe, Gotham and Atwoman's city are somehow connected. Batman discovers a link between some strange occurrences in Gotham and events in Atwoman's city. He travels there to investigate and meets Atwoman. Together, they embark on a journey to uncover the mystery behind this connection. Along the way, they encounter different cultures and villains specific to her city, which makes for an interesting dynamic as they try to combine their skills to solve the problem.
Shego and Kim as unlikely allies could mean that they are brought together by fate. Perhaps a powerful artifact is about to be misused, and they are the only two who know how to stop it. Their initial meetings would be full of tension, but as they start to understand each other's motives, they form a tentative bond.
In this fanfic, Agumon might be a loner Digimon who is used to fighting on his own. Biyomon, on the other hand, is more community - oriented. When they first meet, they don't get along. But as the threat grows, they start to see the value in each other. Agumon learns about the importance of teamwork from Biyomon, and Biyomon learns to be more assertive from Agumon. Their partnership evolves over time as they face different challenges together.
They could be unlikely allies. Maybe in a world where the Pokémon ecosystem is out of balance, Arceus, the symbol of order, teams up with Silvally, a Pokémon with a complex past. Together, they might restore balance, with Arceus guiding Silvally's actions and Silvally using its strength to carry out Arceus's plans.
Bayleef and Latias make for an interesting pair in a fanfic. They could start as unlikely allies. Maybe Bayleef is initially afraid of Latias because of her dragon - like appearance and psychic powers. But as they are forced to work together to solve a mystery in their Pokemon world, like the disappearance of a certain type of Pokemon, they gradually start to trust each other.
They could be unlikely allies in a story where a new threat emerges that neither of them can face alone. This threat could be a powerful interdimensional being. Clark's physical powers and Billy's magical powers combined would be the only way to stop it. They might start off not trusting each other fully, but as the battle progresses, they learn to rely on one another.
A simple fanfiction could be that Cade Yeager discovers a hidden ability within Optimus Prime that no one else knew about. This ability helps them defeat a powerful enemy that was about to destroy the Autobot base on Earth.
One possibility in Tinkerbell - Vidia fanfiction is that they form an unlikely alliance. Vidia, known for her independence, might find herself in a situation where she needs Tinkerbell's help. For instance, if she gets trapped in a part of the forest she's not familiar with and Tinkerbell uses her tinkering skills to free her. This could be the start of a new friendship.
They could be unlikely allies in a fanfiction. Agent 8, being new to the scene, might initially be distrusted by Agent 3. But as they face a common enemy, they start to work together. For instance, a powerful foe emerges that neither can defeat alone.
The idea of an unlikely alliance in a Batman Robin Ray fanfic can be really exciting. Batman is used to working alone or with Robin in the dark alleys of Gotham. Ray might be from a different kind of world, maybe with more of a scientific or otherworldly origin. When they come together, their different fighting styles and mindsets would clash at first. But as they get to know each other better, they realize that they can use each other's strengths. For instance, Ray's knowledge of advanced technology could help Batman upgrade his gadgets, while Batman's combat experience could teach Ray how to better defend himself in a fight.