In the Pokémon world, Naruto's ability to endure hardships would help him in training his Pokémon. His existing combat experience would translate into better battle tactics. He could use his transformation jutsu to disguise himself and his Pokémon, which could be useful in sneaking up on opponents or escaping dangerous situations. His ability to learn quickly would allow him to master the skills needed to be a great Pokémon trainer, like understanding Pokémon types and their strengths and weaknesses.
Naruto's shadow clone jutsu would be a great advantage. He could send clones to explore different areas in the Pokémon world to find rare Pokémon. His chakra control could also be used to communicate with Pokémon on a deeper level. He might be able to sense their emotions and needs better. His ninjutsu skills could be combined with Pokémon attacks to create unique battle strategies. For example, he could use his fire - based jutsus to enhance the power of a fire - type Pokémon's attack.
Well, he'd probably try to use his ninja skills in the Pokémon world. Maybe he'd use his speed to catch Pokémon faster than anyone. He could also use his shadow clone jutsu to battle multiple Pokémon at once.
His combat abilities would become more diverse. Madara could teach him new forms of taijutsu and ninjutsu. For example, Naruto might learn some of Madara's signature space - time ninjutsu, which would give him an edge in battles. His chakra control would also improve as Madara is very proficient in chakra manipulation.
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 would likely have the Sharingan. This would give him the ability to copy jutsu just by seeing them, and also predict his opponents' moves. His combat skills would be enhanced as he could use the Sharingan's powers during battles.
His abilities would be enhanced greatly. He could have better chakra control. For instance, he could use chakra more efficiently and might be able to perform jutsu with less effort. His physical abilities like strength, speed and agility would also improve. He could run faster than normal ninjas and jump higher.
His chakra system might interact with the ambient energy in the Marvel Universe in strange ways. For instance, his rasengan might become more powerful or have different effects. Maybe it could disrupt the energy fields of some of the Marvel villains like Magneto's magnetic fields.
Naruto's chakra could be affected in different ways. Maybe his chakra would take on some properties of the Xenomorphs' acidic blood. So, when he uses certain jutsu, it could have an acidic effect as well. Also, his ability to sense danger could be enhanced. The Xenomorphs have a natural sense of stealth, and Naruto could inherit this, making it even harder for enemies to surprise him. He could also use his shadow clones in more creative ways, like using them as decoys to draw out the Xenomorphs' attacks and then counterattack.
His ninjutsu might be used in different ways. For instance, his Rasengan could be modified to work with the local materials or energy sources in Tifa's world. His ability to move quickly and stealthily would still be useful, but he might have to adapt to new terrains and environments. Maybe he'd use his chakra to enhance Tifa's fighting skills too.
Naruto's fighting style would evolve significantly. He would no longer just rely on his brute strength and the Nine - Tails' chakra. With the Eternal Mangekyou Sharingan, he could use powerful genjutsu and ninjutsu unique to the Sharingan. He might start to use more stealth and precision in his attacks. His training would also change as he has to master the new abilities. He would probably study Uchiha history and techniques more, which would make him more well - rounded as a ninja. This new power would also bring out a more serious side of Naruto, as he now has the responsibility of using such a powerful ability for the good of the village and the ninja world.
If Naruto was trained by Danzo and joined Team 7 in a fanfic, his abilities would change significantly. Danzo's training would probably give him a more strategic mindset. He could be more proficient in using weapons and stealth. In Team 7, he'd learn to coordinate with Sasuke and Sakura. His chakra control might improve in different ways, and he could develop new jutsu that are a combination of what he learned from Danzo and what he discovers while on missions with Team 7.