Well, it might enhance his physical strength a great deal. The dragon could teach him unique combat moves, like some dragon - style strikes. Also, his chakra control could improve as the dragon might have special techniques for that.
His training with the dragon would likely have a huge impact on his abilities. For starters, the dragon could introduce Naruto to new forms of energy manipulation. This could be something completely different from the regular chakra he's used to. It might also improve his speed and reflexes. Since dragons are often depicted as powerful and fast creatures, they could pass on some of those traits to Naruto during training. Maybe Naruto would learn to fly or at least jump much higher than before, which would be a great advantage in battles.
The training could also change Naruto's mental approach to battles. Since Ameyuri Ringo may have a different combat philosophy, Naruto might start to think more strategically. He could learn to analyze his opponents better before jumping into action. This would make him a more well - rounded fighter. Instead of just relying on his brute strength and the Nine - Tails' power, he could use his wits more often.
In this fanfiction scenario, Shaak Ti's training could completely revolutionize Naruto's abilities. Firstly, her knowledge of different forms of combat and strategy could give Naruto new perspectives on fighting. He may start to use his shadow clones in more strategic ways rather than just for brute force attacks. Moreover, the mental training aspect that Shaak Ti would bring could help Naruto control his emotions better during battle, which in turn would make his decisions more rational and his actions more effective. This could lead to an overall upgrade in his combat effectiveness and his standing among the ninja community.
Naruto would become more confident in his abilities. With Kushina's training, he would have a better understanding of his Uzumaki heritage and the power that comes with it. This new - found confidence would show in his battles and his interactions with others.
It also improves Naruto's skills a great deal. He becomes better at combat and using his ninja techniques. For example, his Rasengan might be more powerful or more easily controllable after Iruka's training. Moreover, Naruto's confidence grows under Iruka's guidance. He no longer doubts himself as much and is more willing to take on challenges.
One possibility in this fanfiction could be that Naruto gains new and unique combat skills. Monkey D. Dragon is known for his revolutionary ideas and powerful abilities in the 'One Piece' world. Under his training, Naruto might learn different ways of strategizing and approaching battles, perhaps incorporating some of the more unorthodox fighting styles from the 'One Piece' universe. This could lead to Naruto becoming even more formidable, not just in terms of his ninjutsu, but also in his ability to lead and inspire others in a different way, much like how Dragon has an impact on the 'One Piece' world.
If Naruto was trained by Shang Tsung, his abilities would likely become much more diverse. Shang Tsung has a lot of knowledge about different fighting styles and dark magic. Naruto might learn some sneaky and underhanded tactics which are not typical in his usual ninja training. His chakra control could also be enhanced in new ways, perhaps to mimic some of Shang Tsung's shape - shifting abilities on a basic level. For example, he could use his chakra to change his appearance slightly to deceive opponents, adding a whole new dimension to his combat skills.
If Naruto was trained by Sun Wukong, his physical abilities would likely improve greatly. Sun Wukong is known for his superhuman strength, speed, and agility. Naruto could learn to move faster and hit harder. Also, Sun Wukong's ability to transform might influence Naruto. Naruto already has his own transformation abilities with the Nine - Tails, but he could learn new forms or ways to transform more effectively from Sun Wukong.
They probably develop a mentor - student relationship. The dragon being the mentor guiding Naruto's growth.
The training by death would likely toughen Naruto up both physically and mentally. He'd probably have a darker, more determined edge to his character. He might be more solitary in his training, spending more time alone to master the skills death has taught him. This could make him seem a bit more distant to his friends initially, but in the long run, it would make him a stronger and more reliable ally.
His speed would increase a great deal. Whis is very fast and could teach Naruto how to move more swiftly. Also, Naruto's chakra control might be enhanced, allowing him to perform more complex jutsus with less effort.