Deadpool would be an obvious choice. He and Wolverine already have a history in the comics. Their interactions are always filled with humor and chaos. In a fanfiction crossover, they could be on a mission together, with Deadpool constantly breaking the fourth wall and Wolverine getting increasingly frustrated, all while they take on a powerful villain like Cable.
Storm from the X - Men would be a great addition. She has control over the weather, which could create some really interesting scenarios when combined with Wolverine's combat skills. For example, she could create a lightning storm while Wolverine battles enemies in the rain, using the flashes of lightning to his advantage.
Captain America. He represents the more patriotic and morally upright side of superheroes. When paired with Wolverine, who is more of a loner and has a darker past, it would create a contrast. They could work together to fight a common foe, like Hydra, with Captain America leading the strategic side and Wolverine doing the more up - close and dirty fighting.
In a crossover with Hannah Montana, obviously Miley Stewart as Hannah Montana herself. She could be in Seattle for a secret concert and needs iCarly's help to promote it without revealing her identity. It would be fun to see Sam trying to keep Hannah's secret while also being her usual wild self around her.
In a crossover with the Lord of the Rings, Aragorn could be an interesting choice. He could bring his leadership skills and combat expertise to Los Santos. The GTA 5 characters might initially be skeptical of his noble ways, but they could learn from him. He could also help them fight against a new evil force that has emerged in the city, perhaps an ancient and powerful gang with dark magic - like abilities.
If it was a crossover with The Evil Within, Sebastian Castellanos would be a great character to include. His detective skills and his ability to handle the nightmarish creatures in his own game could be useful in the Outlast 2 world. He could team up with the Outlast 2 character to solve the mysteries behind the horror. Also, Pyramid Head from Silent Hill could be a terrifying addition. His presence alone would heighten the sense of dread in the Outlast 2 crossover story.
Definitely Goku. Their previous encounters in the Dragon Ball series make it a natural choice. Their power levels and different fighting styles would create great tension and action in the story.
Well, if you're doing a crossover with '101 Dalmatians', Cruella de Vil could be an interesting addition. She might see the Aristocats as a new target for her fur coats, creating a whole new conflict for the cats to face. And the Dalmatians could be allies of the Aristocats, helping them outwit Cruella.
In a crossover with 'Moana', Moana herself would be a great addition. She is brave and adventurous, just like Mei. Moana could help Mei understand her own identity better. Maybe they could go on a journey together on Moana's boat, and Mei could learn from Moana's connection with the ocean and her own culture. It would be interesting to see how Mei's red panda form reacts to the ocean environment.
If it's a crossover with a racing game, characters like Need for Speed's main racers could be included. They could have races against the Saints in the streets of the Saints Row city. It would be a high - speed, action - packed addition to the fanfiction.
I think Gandalf from 'The Lord of the Rings' would be an excellent choice. He has his own form of magic and is a very wise character. Combining him with Harry in a godlike crossover could lead to some amazing adventures. Another good character could be Yoda from 'Star Wars'. His connection to the Force and his wisdom could interact interestingly with Harry's world of magic.
In a crossover with 'Naruto', Naruto himself would be a great addition. His positive and determined attitude could contrast with Tomoe's more reserved nature. And his powerful ninja skills could come in handy when facing some of the demons in the Kamisama Kiss world. Sakura could also be there, and she might bond with Nanami over their strong wills.
Maybe some other popular YouTubers. For instance, PewDiePie could be a fun addition. Their different personalities could lead to some really entertaining interactions, like PewDiePie trying to get Theodd1sout to be more outgoing in the fanfic world.