One idea could be that Naruto discovers Brandish in a parallel universe and takes her under his wing. Maybe he sees her potential and trains her in his unique ninja ways.
Yes, there are quite a few. You can start by looking on popular fanfiction websites like FanFiction.net or Archive of Our Own. Some of them might focus on their relationship development, perhaps starting from an unexpected encounter and gradually leading to deeper feelings for each other.
The potential for unique storylines. Since they come from different backgrounds within the Fairy Tail world, their love story can involve a lot of exploration. They could have to deal with rivalries or misunderstandings that add depth to the story. For example, Brandish's past actions and Natsu's loyalty to his guild might initially cause friction but then lead to a more passionate relationship. It also gives the authors a chance to explore different aspects of the Fairy Tail universe, like the power dynamics between different characters and groups, which makes the fanfiction more interesting.
One common theme is redemption. Given Brandish's complex backstory in Fairy Tail, many fanfictions focus on her finding a way to redeem herself or make up for her past actions.
One great 'Fairy Tail Brandish' fanfiction is 'Brandish's New Beginning'. It explores Brandish's character development after the main events in Fairy Tail. It has a great plot that dives deep into her past and how she's trying to find her place in the new world order of the Fairy Tail universe.
The plot is crucial. It could be something that ties in with the existing Fairy Tail lore but also takes it in a new direction. Maybe it involves Brandish in a time - travel adventure where she has to change the past to save the future of Fairy Tail. This kind of unique plot idea can make a fanfiction really stand out.
One common theme is adventure. Since Fairy Tail is all about magic and quests, many fanfics in this category will have the oc and Brandish going on adventures together. Another theme could be friendship. They might start as strangers and gradually become friends as they face various challenges. And of course, romance is also a popular theme, with the oc and Brandish developing feelings for each other over time.
One popular plotline could be Brandish and Natsu teaming up against a powerful common enemy. They might start off distrusting each other at first, but as the story progresses, they learn to respect and rely on one another. Another could be a story where Brandish has some sort of magic problem and Natsu, with his unique fire magic, helps her solve it. It could also be a story set in an alternate universe where they are on a quest together to find a powerful magical artifact that could change the fate of the Fairy Tail guild and Brandish's own people.
It could involve Naruto teaching Brandish about his ninja village and the importance of comradeship. Brandish might learn to use some of Naruto's ninja skills in addition to her magic.