A popular one is 'Naruto in the World of Familiar of Zero'. In this fanfic, Naruto is transported to the world of 'Familiar of Zero'. His ninja skills and determination make him stand out in this new world filled with magic and nobles. He forms unexpected alliances and has to face different challenges compared to his original world.
There's also 'Zero's Familiar and the Ninja'. This fanfiction focuses on how a character from 'Familiar of Zero' becomes involved with the ninja from 'Naruto'. It delves into the cultural shock between the two very different worlds, as well as the development of relationships between characters from both universes. It's a fascinating read for fans of both series.
One great 'Naruto x Familiar of Zero' fanfiction is 'The Crossroads of Konoha and Halkeginia'. It combines the unique magic system of 'Familiar of Zero' with the ninja world of 'Naruto' in an interesting way. The main character, who has knowledge of both worlds, tries to bring new changes to both.