For Naruto, characters like Kakashi could be great to include. Kakashi's wisdom and experience would add depth to the story when combined with Naruto's energy. In Rossweisse's case, characters from her own world who have strong magical abilities could be paired with her. They could support her in her adventures with Naruto.
Sasuke could also be an interesting character to pair with Naruto in this fanfiction. Their complex relationship would bring a lot of drama and action. For Rossweisse, a powerful mage who has a different view on magic than her could be paired. This would create interesting conflicts and discussions about magic within the story.
Well, if we consider a crossover, characters like Goku from Dragon Ball Z would be a great match. Goku's love for fighting and his super - strong powers would be exciting to combine with Naruto and Izumi's ninja skills. Then there's Natsu from Fairy Tail. His fiery personality and magic abilities would bring a new flavor to a story with Naruto and Izumi. And also, Kirito from Sword Art Online. His experience in virtual worlds and combat skills could lead to some really unique interactions when paired with Naruto and Izumi in a crossover story.
Kakashi could be a great addition. He could act as a mentor figure during their tag - team adventures. His experience and unique jutsu like the Chidori could complement Naruto and Sasuke's skills. For example, in a battle, Kakashi could use his Sharingan to analyze the enemy's moves while Naruto and Sasuke execute their attacks.
Another character could be Kakashi. Kakashi's wisdom combined with Byakuya's combat skills and Naruto's determination would make for a really engaging story. Kakashi could study Byakuya's techniques and try to incorporate some of that into Naruto's training, while also trying to understand Byakuya's motives in the Naruto world.
I think Mario and Hinata would be an interesting pair. Hinata's shy but strong - willed nature could contrast with Mario's always - positive and heroic attitude. And Mario could help Hinata become more confident in this cross - over scenario. Another good pair could be Toad and Shikamaru. Toad's small but brave self and Shikamaru's intelligence would make for an engaging dynamic.
Sasuke could be a great addition. His complex relationship with Naruto already exists and adding Touka to the mix could create some really interesting dynamics. They could all be involved in a high - stakes battle against a new and powerful enemy.
Sasuke could also be an interesting character to pair with Gohan. Sasuke's brooding nature and his quest for power could contrast with Gohan's more altruistic motives. They could have some intense battles and then later come to understand each other better. Maybe Gohan could help Sasuke see a different path than his revenge - driven one.
Naruto himself could be a great character to pair with Magneto. Their different powers and personalities would create an interesting dynamic. Naruto's positive and determined attitude could contrast with Magneto's more serious and sometimes harsh nature. Also, they could learn from each other's combat styles and strategies.
Well, Hinata could be paired with Guren in some fanfiction. Hinata's shy yet strong - willed nature could contrast with Guren's more assertive personality. It could lead to stories about friendship or even a mentorship kind of relationship. Kiba and his dog Akamaru could also be paired with Guren. Their teamwork - based fighting style could add a new dimension to stories involving Guren in the Naruto fanfiction world.
Naruto and Jack would be a great pair. Naruto's energetic and never - give - up attitude would mesh well with Jack's determination in Kickin It. They could learn a lot from each other, like Naruto teaching Jack about chakra control and Jack teaching Naruto some advanced martial arts moves.
Another good pair could be Kakashi and Eminem. Kakashi is a very laid - back yet highly skilled character. His calm demeanor could contrast well with Eminem's energetic and often angry - inspired lyrics, leading to some unique exchanges and perhaps even Kakashi learning a thing or two from Eminem about expressing emotions.