Well, a plotline might be that Ayane is sent to Konoha on an exchange program. Naruto is assigned to show her around. At first, they don't get along, but as they share their life stories and experiences, they start to bond. There could be a sub - plot about Naruto's struggle to balance his feelings for Ayane with his duties as a ninja, and how they overcome obstacles in their relationship together.
A plotline could involve Ayane being a mysterious figure who has some unique power. Naruto is intrigued by her and tries to get to know her better. As they interact more, they find themselves falling in love. Maybe there's also a villain who wants to use Ayane's power for evil, and Naruto has to protect her.
Well, one possible plotline could be that Ayane, for some reason, enters Naruto's world. Maybe she's on a mission or has been transported there accidentally. And then, through a series of events, they start to develop feelings for each other that lead to the more 'lemon' - ish aspects of the story. However, this would require a lot of world - building to combine their two different universes.
A plotline could involve a magical artifact that has the power to change the fabric of different universes. Naruto, Mirajane, and Erza are all drawn to it for different reasons. Naruto wants to use it to protect his village, Mirajane to protect her guild, and Erza for the sake of justice. As they fight over the artifact at first, they realize that a greater evil is trying to use it for destruction, so they join forces. Along the way, they learn about each other's worlds and cultures, and their relationships grow.
A possible plotline could be that Naruto is transported to Maleficent's world. He might initially be seen as a threat but then prove himself to be an ally. Together, they could fight against the dark forces in Maleficent's world that are trying to take over the entire realm.
Maybe in a 'naruto x cheetah fanfic', the cheetah is a spirit animal that Naruto encounters during a spiritual journey. The cheetah imparts some special wisdom or power to Naruto, which he then uses to face his enemies back in the real world. This could involve Naruto having to master this new power while also dealing with the politics of the ninja villages.
One possible plotline could be that Naruto somehow ends up in Quinella's world. He might initially be confused but then use his ninja skills to navigate the new environment. Quinella could be intrigued by him and they form an unlikely alliance against a common enemy in her world.
In a 'naruto x lilith fanfic', a plotline could be that Lilith is a mysterious figure who has been observing the Naruto world for a long time. She finally reveals herself to Naruto and offers to train him in a new and powerful form of jutsu. As they train together, a bond forms between them, which could lead to various story developments, such as facing off against other powerful foes or dealing with the politics within the ninja villages.
One possible plotline could be a love triangle where Naruto is initially torn between Hinata's quiet devotion and Ino's bold personality. Another could be that Hinata and Ino start as rivals for Naruto's affection but then end up becoming friends as they realize they have more in common than they thought. Maybe there's a plot where Naruto goes on a mission with both Hinata and Ino, and during the mission, they have to rely on each other and their relationships evolve. It could also involve a story where Ino uses her mind - control jutsu accidentally on Naruto and Hinata has to save him, which then deepens Naruto's feelings for Hinata.
A third plotline could be that Fem Zabuza is a time - traveler. She travels back in time and meets a young Naruto. She decides to train him, seeing his potential. As they train together, a bond forms between them. But her presence in the past also starts to change the future in unexpected ways, and they have to deal with the consequences while also exploring their relationship.
One possible plotline could be Naruto being transported to the Army of Two world and having to learn how to work with the partners in that world. He could use his ninja skills to help them in their missions.
A plotline might involve a magical accident that merges the two universes. Naruto and Harley Quinn are forced to work together to separate the universes again. Along the way, Naruto could teach Harley Quinn about the value of friendship and loyalty, while Harley Quinn shows Naruto how to be more spontaneous. Or perhaps Harley Quinn is being hunted in the Naruto world by some ninja who mistake her for a dangerous threat, and Naruto has to protect her.