Well, in a 'Naruto learns nen' fanfiction, perhaps Naruto is sent to a different dimension where nen is the dominant power source. There, he has to learn nen to survive and find his way back home. He starts from the basics, learning about the different nen types like Enhancer, Transmuter etc. As he progresses, he combines his knowledge of ninjutsu with nen, creating unique and powerful attacks.
A traveling nen master could be Naruto's mentor. This master could be on a journey to spread the knowledge of nen. He crosses paths with Naruto and decides to teach him. The master might have a strict teaching style, pushing Naruto to his limits, but also guiding him carefully through the complex world of nen.
It could be Hagrid. He's always had a connection to strange and powerful things. Maybe he stumbles upon the knowledge of nen during one of his trips in the magical forest and then passes it on to Harry.
In a 'harry potter learns nen fanfic', it could be that during his time at Hogwarts, a new exchange student from a far - off land where nen is known arrives. This student becomes friends with Harry and teaches him about nen. Harry then tries to combine nen with his existing magical abilities, like using nen to make his Patronus more powerful.
Perhaps in this fanfiction, Naruto is born with the ability to use Nen, but it lies dormant until he faces a great danger. When it awakens, he has to learn to control it quickly. He might struggle at first, as Nen is very different from chakra. But with the help of his friends and his own determination, he masters Nen and uses it to protect Konoha from a new and unexpected threat that normal ninja techniques can't handle.
He might learn a time - traveling jutsu. This would be really cool as it could allow him to go back and change certain events in the Naruto world, or gain knowledge from the past to use in the present battles.
Well, it could start with Naruto being born female in this fanfiction universe. As she grows up, she discovers the power of Nen. Maybe she goes on a journey to learn more about it, facing challenges along the way similar to those in the Naruto world but with the added element of Nen. For instance, she might have to use Nen to defeat enemies that the normal Naruto - style jutsu can't handle.
A great Naruto nen user fanfiction could involve a crossover with the Hunter x Hunter world. In this story, Naruto and his friends are transported to the Hunter x Hunter universe and have to learn nen in order to survive and find a way back home. Along the way, they meet the various characters from Hunter x Hunter and learn about the different nen abilities.
Another option could be to check Naruto - related forums. There are often threads where fans discuss and share their favorite fanfictions. Some well - known Naruto forums might have users who are into this specific concept of 'Fem Naruto Knows Nen' and could point you in the right direction.