A possible plot is that female Naruto enters a dimension full of mythical creatures. She has to befriend some of them to learn about this new world and find a way to return to her own. For example, befriending a dragon that can help her fly over the strange terrains.
Maybe she lands in a dimension where there are different types of chakra with new and unknown properties. She spends her time exploring and mastering this new chakra system, all while trying to figure out how to get back to her dimension. She could meet other 'Narutos' from different parallel universes in the process.
Perhaps in this different dimension, female Naruto is a princess. But she still has her ninja spirit. She uses her skills in a different way, like using her agility to outwit court conspirators. And she might even start training the palace guards in her ninja ways secretly.
In fanfiction, if Naruto is sent to a different dimension, he might face all kinds of strange new powers and enemies. For example, he could encounter magic that is completely different from chakra. He would have to quickly adapt to survive. Maybe he'd find allies who are also lost in this new dimension and together they'd try to find a way back home while also dealing with the local threats.
In this type of fanfiction, a possible plot is that Naruto is sent to a dimension where time moves differently. He might age at a much faster rate, and he has to quickly master the ways of this dimension to find a way to reverse the time effect on him. Another cool plot could be that he lands in a dimension that is a mirror image of his own, but with opposite personalities for everyone. So he has to deal with a Sasuke who is overly friendly and a Kakashi who is always serious, which makes for a really strange and challenging adventure.
A possible plot could be that female Naruto is targeted by a group who don't want her to succeed in the Chunin Exams. They try to sabotage her at every turn, but she overcomes their obstacles with her determination and the help of her friends. Another plot could be that she discovers a hidden power during the exams that she didn't know she had, which gives her an edge over the other competitors.
One idea could be Naruto getting trapped in a dimension where chakra doesn't exist, and he has to learn new forms of power. Another could be a dimension where the Akatsuki are the heroes, and Naruto has to figure out how to co - exist or change that world. Or perhaps a dimension where all the dead characters are alive again, but in different roles, like Itachi as a rogue ninja fighting against Konoha.
In a 'Naruto is Ranma' fanfiction, a possible plot could involve a powerful villain who wants to use the powers of both Naruto's ninja world and Ranma's world for evil. Naruto and Ranma would then have to team up, along with their respective friends. Naruto could teach Ranma's friends some basic ninja skills, and Ranma could show Naruto's friends how to handle his transformation curse. This would lead to a lot of comical and action - packed situations as they fight the villain and try to save both worlds.
One plot could be that Naruto is discovered by a traveling minstrel who sees his potential and decides to train him. As he becomes a singer, he uses his new - found fame to promote peace between the villages, using his songs to tell the stories of the ninja world and the importance of unity.
A possible plot could be that Naruto's chakra system is damaged, which leads to his legs being paralyzed and him using a wheelchair. He then embarks on a journey to find a cure, facing various challenges along the way. This could involve him meeting new characters who either help or hinder his quest.
One possible plot could be that Naruto is created by some sort of scientific experiment gone wrong in the Naruto universe. He then has to deal with the fact that he's different from other ninjas. Another plot could be that someone tries to use Naruto's 'Frankenstein - like' nature to gain power, and Naruto has to fight against that exploitation.
She could travel to a dimension where all the ninja villages are united. Naruko would be amazed at the peace and cooperation and might try to bring this concept back to her own dimension. It would be a story about her learning from this utopian - like place.