A great Usopp crossover fanfiction could involve the world of Star Wars. Usopp might be a mechanic on a spaceship, using his inventive skills to fix and improve the ship's systems. He could also encounter some of the iconic Star Wars characters like Han Solo or Chewbacca. Or, a crossover with the Avatar: The Last Airbender universe. Usopp could learn bending techniques and use his slingshot in combination with them. For example, he could create a slingshot that can launch water or fireballs. Also, a crossover with the Pokémon world would be interesting. Usopp could be a Pokémon trainer, using his Pokémon to help in his adventures while also using his own unique skills.
One idea could be a crossover between Usopp and the world of Harry Potter. Usopp could be a wizard who uses his creativity and skills to create unique magical items and tricks, much like his inventions in his own world. Another could be a crossover with the DC universe, where Usopp teams up with the Green Arrow. They both have skills with ranged weapons and could learn from each other. A third idea is a crossover with the Final Fantasy series. Usopp could find himself in a world full of magic and strange creatures, using his wits to survive and help the characters there.
Perhaps there's a mission where Sanji and Usopp have to go undercover as a couple in a high - society event. At first, it's just for the mission, but as they play their parts, they start to feel real emotions. They have to navigate through the social intrigue, all while dealing with their own growing feelings for each other. This situation could lead to a lot of cute and romantic moments in the fanfiction.
In some 'usopp fanfiction', he might be the key to solving a mystery on the ship. Maybe there are strange occurrences that only his unique perspective and skills can figure out. This could involve his talent for creating gadgets and his sharp observational skills, which are often overlooked by others but prove crucial in these fictional scenarios.
You can start by looking on popular fanfiction websites like Archive of Our Own (AO3). It has a large collection of fanfictions from various fandoms, including One Piece (where Usopp is from), and likely has some great Usopp crossover fanfictions. Another option is FanFiction.net. It's been around for a long time and has a wide range of fan - created stories, so you might find some interesting Usopp crossovers there as well.
One popular luffy x usopp fanfiction might be 'The Unbreakable Bond'. It delves into their friendship in a more in - depth way, showing how they support each other during tough times on their adventures. Another could be 'Shared Dreams', which focuses on their common goals and how they inspire one another to reach for the stars. There's also 'Adventure Anew' that takes their relationship and throws them into new and exciting scenarios.
One idea could be that Sanji and Usopp team up for a cooking competition on the ship. Sanji brings his world - class cooking skills and Usopp uses his creativity to come up with unique presentation ideas. Another could be a situation where they get lost on an island together and have to rely on each other's skills, Sanji for survival cooking and Usopp for building shelters and creating distractions against potential threats.
Well, he could time - travel to a point where the Straw Hats first formed but he's the only one who remembers the future. This would lead to some really funny and interesting situations. He might try to prevent some of the early hardships they faced, like the fight with Buggy. Or perhaps he travels to a time during the Void Century and discovers secrets that could change the course of the current One Piece world. He then has to figure out how to bring this knowledge back to his own time without causing chaos.
One idea could be a story where Sanji and Usopp get stranded on a strange island together. Sanji has to rely on Usopp's creativity to find food sources that are not immediately obvious, while Usopp depends on Sanji's combat skills when they encounter dangerous creatures on the island. This would force them to bond and understand each other better.
One idea could be a Jessie crossover with a superhero universe. Jessie could use her skills and charm to team up with superheroes, perhaps helping them understand the value of friendship like she does with her friends in her own show. Another could be a crossover with a fairy - tale world where she brings her modern - day smarts to solve problems in a magical realm.
For a Matilda crossover fanfiction, consider a crossover with The Secret Garden. Matilda could help bring the garden back to life with her unique abilities. Or, a crossover with Charlie and the Chocolate Factory. She could use her smarts to solve some of the strange mysteries in Willy Wonka's factory. Also, a crossover with Peter Pan would be interesting. Matilda could befriend Peter and the Lost Boys and use her powers to fight Captain Hook.
One idea could be an Ansem crossover with a popular fairy - tale world. For example, crossing Ansem with the world of Alice in Wonderland. Ansem's dark and mysterious nature could contrast well with the whimsical and often illogical world of Wonderland. He could be on a quest for some dark power hidden within the Wonderland, interacting with characters like the Cheshire Cat or the Queen of Hearts in his own devious way.