The cultural clash is really interesting too. Naruto comes from a world with a very different culture compared to the DxD world. Adding Devil Fruits into the mix makes it even more complex. For instance, Naruto's values of loyalty and hard work might interact in unexpected ways with the more morally ambiguous elements of the DxD world and the power - hungry nature often associated with Devil Fruit users.
One popular 'Naruto Devil Fruits DxD Fanfic' is 'Naruto in DxD with Devil Fruits'. It combines the unique powers from Naruto's world and the Devil Fruits concept from One Piece into the High School DxD universe in an interesting way.
He could eat the Pika Pika no Mi (Glint - Glint Fruit) which gives the power of light, allowing him to move at the speed of light and create powerful light - based attacks. And perhaps the Yami Yami no Mi (Darkness - Darkness Fruit) which can absorb other attacks and create a gravitational pull. Combining the powers of light and darkness would be quite a unique and powerful combination for Naruto in this fanfiction.
The powers of devil fruits can be integrated by having characters discover them in a strange new land that has a connection to both the Naruto and One Piece universes. For example, a portal could open up and Naruto and his friends find a devil fruit tree. They then have to figure out how these new powers work within the context of their own ninja abilities. Maybe the devil fruit powers can be combined with chakra to create even more powerful attacks.
Well, he might gain new powers which could make him more confident. For example, if one of the devil fruits gives him the power of flight, he would feel more powerful and it could change his approach to battles. He might become a bit more adventurous too, as he explores the limits of his new abilities.
There might be a fanfic where Naruto is reincarnated as a weak devil in the DxD world. In such a story, he has to use his ninja skills and knowledge to survive in a world full of powerful devils and other supernatural beings. The story could explore how his chakra system works in a world dominated by magic, and how he overcomes the prejudice against his weak - devil status.
The character development can be really engaging. The weak devil, starting from a position of weakness, can grow and change throughout the fanfic. Maybe they start as a bullied character but end up being a strong ally. And Naruto's presence can be a catalyst for this change. Also, the exploration of the DxD world from Naruto's perspective, as he tries to understand the devils and their society, adds depth to the story.
Another fanfiction concept could involve Naruto being sent to the One Piece world through some kind of strange ninja jutsu gone wrong. There, he eats a Logia Devil Fruit that allows him to turn into water. He teams up with the Straw Hat Pirates and uses his water - based powers, along with his ninja knowledge of chakra control, to help them in their adventures. For example, he could use his water form to put out fires on the ship or create water - based defenses against enemies.
One possible scenario in this fanfiction could be Naruto having his unique ninja skills in the Highschool DxD world. His godlike abilities might make him stand out among the devils and other supernatural beings. He could use his shadow clone jutsu for various strategic purposes, like infiltrating devil strongholds or getting out of tricky situations during the school's chaotic events.
There could well be. Fanfiction writers often like to explore crossovers and unique concepts. However, not all fanfic writers might be interested in combining Naruto with 'Highschool DxD' in a certain way, so there are likely to be some that fit the 'Naruto not a devil highschool dxd fanfiction' idea. You might have to dig a bit through different fanfic archives to locate them.