A really cool one is 'Smash Bros Meets Pokemon Universe'. In this fanfic, the Smash Bros characters end up in the Pokemon world. It's full of fun encounters as they try to figure out how things work in this new environment, and there are some epic battles against powerful Pokemon.
First, know the characters well. Each character in Super Smash Bros Ultimate has unique abilities and personalities. For example, Mario is brave and resourceful. Then, create an interesting crossover concept. Maybe it could be the Smash Bros characters in a Final Fantasy world. Keep the story engaging with lots of action and dialogue.
One popular theme is the unexpected team - ups. For example, characters from different game universes that you would never think would work together end up being great partners in the fanfiction. This can create really interesting and unique storylines.
One idea could be a crossover with a classic RPG like Final Fantasy. Characters from Final Fantasy could enter the Super Smash Bros universe and bring their unique abilities. For example, Cloud could use his Omnislash. Another idea is a crossover with an anime like Naruto. Naruto characters would add a whole new dynamic with their ninja skills. And a third idea could be a crossover with a horror game, like Resident Evil. The spooky elements and unique weapons of Resident Evil characters would make for a very different kind of Super Smash Bros fanfic.
First, decide which two or more universes you want to crossover. For example, if you choose Super Smash Bros and Mario Kart, think about how the characters and elements from both will interact. Then, come up with a basic plot. It could be a tournament where characters from both universes compete. Next, create some unique scenarios. Maybe the Mario Kart tracks are now part of the Smash Bros battle arenas. Start writing simple descriptions of the characters and their reactions to this new crossover world.
First, choose your characters. Decide which characters from different Super Smash Brothers games you want to feature. Then, think of a simple plot like a tournament or a quest they all embark on together.
Another idea is that the Smash Bros characters are transported to the Naruto universe. They'd have to adapt to the ninja world. For example, Mario might try to use his jumping skills on the rooftops of Konoha, while Link could use his swordsmanship against ninja foes. It would be really interesting to see how they interact with the Naruto characters and learn about chakra.
Naruto and Kirby would be really interesting. Kirby could copy Naruto's abilities, like his running speed or his ability to use chakra. And Naruto could be amazed at Kirby's cuteness and his unique way of fighting, like inhaling enemies. They could have a really fun dynamic together.
The crossovers themselves. When characters from different games meet, like Link from Zelda and Cloud from Final Fantasy in Smash Bros, it creates a whole new dynamic. It's exciting to see how their different abilities and personalities interact.