If Naruto is trained as a Sith in fanfiction, his story arc would deviate from the original in many ways. For starters, his goals would change. Instead of protecting the village and its people, he could be more interested in subjugating them. His relationships would be in shambles as he becomes more power - hungry. His training as a Sith would introduce new elements like learning Sith magic which would put him at odds with the traditional ninja world. His story would then be about his fall from grace and either his redemption or his total embrace of the dark side.
His story arc would become much darker. Instead of aiming to be a respected Hokage, he might aim to rule over the ninja world with an iron fist like a Sith Lord. His friends might turn into enemies as they oppose his new, dark ways.
On a more positive note, the Sith Holocron could inspire new ways of thinking. Naruto, being the open - minded person he is, could take some of the concepts from the Holocron, like the Sith's focus on self - improvement (although in a very different way from the dark side), and apply it to his ninja training. He could also try to adapt some of the knowledge to create new jutsu that are more efficient and powerful, but without the dark undertones. This would lead to a new era of ninja development in his world.
His relationships could be strengthened. His friends might be in awe of his new abilities and look up to him more. They could also be a bit jealous at first, but then realize they can all grow together. For example, Sasuke might see Naruto's new powers as a challenge to overcome himself.
Well, it could make him more desperate to catch up. He might become more self - doubting at first. But then, as he realizes his mistake, he could develop a stronger sense of determination to overcome his lack of training. For example, he might start training in more unorthodox ways to make up for lost time.
It could make some relationships stronger. His friends might be in awe of his new powers and look up to him even more. But it could also create some distance, as his new status might make others feel inferior.
Well, Izuku's sentient quirk could make his training more challenging in some ways. Since the quirk has its own thoughts, it might not always agree with Izuku's training methods. There could be clashes between what Izuku wants to do and what the quirk thinks is best. This would force Izuku to find a compromise and develop new strategies for training that satisfy both him and his quirk.
Well, it definitely slows him down. He can't push himself as hard as he usually does. His stamina is lower, so he might not be able to complete his normal training routines.
It could speed up his training significantly. If the jutsu scrolls contain advanced techniques, Naruto can learn from them and gain new skills faster than just relying on his regular training with Kakashi. For instance, if there's a jutsu for enhanced strength, he can add it to his arsenal and become stronger in combat.
Well, in many fanfictions, Naruto's training with Kyuubi gives him a huge power boost. It allows him to access Kyuubi's chakra more easily and effectively. This newfound power can make him more confident in battles, and he may be able to take on stronger opponents. He can also learn unique techniques that are related to the Kyuubi's power, which sets him apart from other ninjas.
Well, Minato could start training Naruto from a very young age. He could pass on his Flying Thunder God Technique, which would give Naruto a huge advantage in combat. Kushina could train Naruto in the ways of the Uzumaki clan, like their strong chakra reserves and sealing techniques. With both of them alive, Naruto's training would be more comprehensive and personalized compared to what he had in the original story.
When Naruto takes off his weights in fanfiction, it could completely revolutionize his training. He might find that he can now train with stronger opponents, like the elite jounin or even the Hokage. This would expose him to different fighting styles and strategies, which in turn would help him grow as a ninja. Also, his physical training could now include more acrobatic and aerial maneuvers that were previously difficult with the weights on. His chakra control might also be affected, as the change in his body's movement could require different levels of chakra distribution. This could lead to him exploring new ways of using his chakra in combat and non - combat situations.