If Naruto was trained by Fairy Tail, his power level would see a huge transformation. Fairy Tail's training focuses on not just physical strength but also emotional and mental growth related to magic. Naruto, with his already strong will, could use this to master new forms of magic. He could learn to tap into the power of Fairy Tail's magic sources, like the Etherion or the Celestial Spirits. This would add a whole new dimension to his power, making him not only stronger in combat but also more versatile in handling different types of threats.
Well, Naruto would probably gain some really unique magical abilities. Fairy Tail mages are known for their diverse magic, and Naruto could combine his chakra skills with something like Fire Magic or Celestial Magic. He might become even more powerful in combat, with new ways to attack and defend.
Naruto's abilities would have to adapt to the Fairy Tail universe's rules. His sage mode, which is based on natural energy, might interact with the natural magic in the Fairy Tail world in strange ways. For example, if there are areas with high concentrations of magic like Ethernano, his sage mode might be overloaded or gain super - charged abilities. His jutsu like the Summoning Jutsu could be seen as a form of summoning magic in Fairy Tail, but he would have to learn how to control and communicate with the summoned creatures in a different way. His ability to use chakra control for things like walking on water might not work the same way, and he would need to figure out how to use magic for similar feats.
The Sage of Six Paths' power is extremely high. In Naruto, he is like a god - like figure. Compared to the strongest in Fairy Tail, like Acnologia, it's hard to say. Acnologia has the power to destroy entire civilizations with his dragon form. But the Sage of Six Paths has the ability to create and manipulate life - force. It could be that in a fanfiction, their powers would be on a somewhat equal level if the writer wanted to create a balanced and exciting story.
A Saiyan's high power level could potentially disrupt the balance in the Fairy Tail universe. Saiyans are known for their extreme combat capabilities. Their power could either be seen as a great asset or a huge threat. For example, in battles against the dark guilds, a Saiyan's raw strength might make short work of the enemies. However, their power might also attract unwanted attention from powerful foes or even make some in the Fairy Tail guild uneasy due to the potential for destruction.
Well, if Kaguya trains Naruto, his power level would likely skyrocket. Kaguya is an extremely powerful being. She could teach Naruto some ancient and powerful jutsu. Maybe Naruto would learn to better control his chakra on a more fundamental level, like how Kaguya uses her chakra in a very different and more refined way compared to normal ninja. This could give him an edge in battles and make him a much more formidable opponent.
Well, it could be that Naruto's arrival in the Fairy Tail universe brings with it some sort of dimensional rift or imbalance. His very presence, being from a different world with different laws of nature, might cause the ground to shake. Just like if you put two incompatible substances together, there could be a reaction. His ninja skills are so different from the magic in Fairy Tail that it might create a sort of chaos that manifests as earthquakes.
Naruto's chakra could be seen as a form of magic in the Fairy Tail world. His ability to use Shadow Clones, for instance, could be combined with a Fairy Tail mage's illusion magic. He could create dozens of clones that are also capable of casting illusions, confusing enemies. His Rasengan could be enhanced with different types of magic, like wind magic to make it even more powerful and destructive.
Naruto's powers have their own unique features. His Sharingan (if he had it in this fanfiction) would give him an edge in perception and combat, which might be different from what the mages in Fairy Tail are used to. But the mages in Fairy Tail have a wide variety of magic types, such as fire magic like Natsu's or ice magic like Gray's. Naruto's powers would need to adapt to this new magical environment. He might be able to create new techniques by combining his ninja skills with the magic he encounters in the Fairy Tail world.
Naruto's power would change in multiple ways if trained by Scorpion in fanfiction. Firstly, his ability to deceive his opponents would increase. Puppets can be used to create illusions and false attacks, and Naruto could master this aspect. Secondly, his power in team battles could be enhanced. He could use puppets to support his teammates from a distance or create barriers. His overall combat style would become more versatile. He wouldn't just rely on his brute strength and chakra - intensive jutsu. Instead, he would have the finesse of Scorpion's puppet - based combat, which could make him a more unpredictable and dangerous opponent in the ninja world.
If Natsu were trained by Acnologia, he might face a moral dilemma. Acnologia is a feared and often seen as an evil force. Natsu has always been on the side of good. So, during the training, he would have to decide whether to follow some of Acnologia's more ruthless ways of using power or stay true to his own values. This internal struggle could add a lot of depth to his character. Also, his relationships with his friends in Fairy Tail might be strained as they might be worried about the influence Acnologia has on him.