His chakra control is another aspect. In DxD, he could use his chakra control to enhance his physical abilities even more than the normal superhuman strength in the DxD world. He could also use it to sense the presence of different beings, similar to how he senses chakra in his own world.
One way is through a reincarnation plot. Naruto could be the reincarnation of a primordial god. So, he has the dormant powers within him that start to awaken in the High School DxD world. This would give him an edge in battles and also make him a target for various factions who either want to use his power or are afraid of it.
The characters' abilities could combine in some really cool ways. For example, Naruto's Rasengan could potentially be infused with the power of a Sacred Gear. This would create a super - powerful attack that has both the destructive force of the Rasengan and the unique properties of the Sacred Gear. Also, the Sharingan from Naruto could be used to analyze and copy the techniques used by the characters in High School DxD. On the other hand, the characters in High School DxD could use their demonic or angelic powers to enhance Naruto's physical abilities, like making him faster or stronger.
Naruto's ability to use chakra could be a game - changer. His shadow clone jutsu could be used for various strategies, like in battles against the devils in High School DxD. When it comes to Moka, Naruto could use his clones to distract her while he tries to understand her vampire powers.
Naruto's God Slayer abilities could completely shift the power balance. For instance, if he has the power to slay gods, he could pose a serious threat to the devils' hierarchy which has some connection to the divine. This would likely lead to various factions either trying to recruit him or eliminate him.
His chakra abilities might be affected by the magic in the DxD world. Maybe his Rasengan could gain some magical properties.
His chakra control might be affected by the different magical energies in the DxD world. Maybe his chakra could interact with the devil or angelic powers in unexpected ways. For example, his Rasengan could gain new properties if combined with devilish power. His shadow clones might also be able to do things like sense magical auras, which they couldn't do in the Naruto world.
He could be a new type of threat or ally in the DxD world. Since Naruto has such powerful abilities, the fallen angels might see him as a potential weapon or a hindrance to their plans.
One idea could be to create a fanfic where Naruto is somehow transported to the world of High School DxD. He could bring his unique ninja skills and chakra system. Maybe he teams up with Issei to fight against a common enemy. For example, a powerful devil or fallen angel that threatens both the ninja world and the DxD universe.
Naruto might also interact with the Juubi on a more strategic level. He could plan with the characters from High School DxD to contain the Juubi first. For example, using the barriers and spells available in the DxD world along with his own shadow clone jutsu to surround the Juubi. Then, they could work on finding a more permanent solution, like using some ancient magic from the DxD universe combined with Naruto's sealing jutsu.
His ability to learn dragon languages and gain new shouts over time would mean that as the story progresses in the fanfiction, his power would keep growing. In High School DxD, the power is often based on birthright or contracts. The Dragonborn's self - made power through his efforts would be a new concept. His dragon - related abilities such as dragon riding could also give him an advantage in mobility, allowing him to quickly move between different areas in the High School DxD world, which could be crucial in battles or strategic maneuvers.