His character would become more aggressive and less empathetic. Since Orochimaru is a power - hungry and often cruel character, Naruto under his control would likely act in ways that are not in line with his usual self. He might be more willing to use force and less likely to try to understand his opponents.
His relationship with Sasuke would definitely change. Sasuke might be initially shocked and confused. He might see Naruto in a new light, not just as a rival but also as someone he needs to protect. Their dynamic could shift from pure rivalry to a more complex relationship with new emotions involved.
Naruto would likely become more secretive. Since Orochimaru is a very private and often devious character, Naruto might pick up some of those traits. He would probably keep things from his friends more often.
Naruto would likely become more secretive. Since Orochimaru's training methods are often not in line with Konoha's values, Naruto would have to hide what he's learning. He might also become more distrustful of others as Orochimaru could instill in him the idea that everyone is out to get him for his newfound power.
Naruto would become more cunning. Orochimaru is a very sly character, and his training would likely rub off on Naruto. Naruto would no longer be as straightforward in his battles and interactions. He might start to think several steps ahead, like Orochimaru does.
It would likely become more complicated. Sasuke has his own history with Orochimaru. If Naruto goes to Orochimaru for power, Sasuke might see Naruto as a rival in a different way. He could be jealous that Naruto is getting power from Orochimaru, or he could be angry that Naruto is making the same 'bad' choice he once did.
Naruto's character would change a great deal. He would be exposed to Orochimaru's world of experimentation and dark magic. This might make him more cynical about the ninja world. Also, he would have to adapt to Orochimaru's strict and often cruel training methods. As a result, he could become more introverted and less trusting of others. His once open - hearted nature might be replaced with a more guarded one.
Naruto's character would likely become more cynical. Orochimaru's ways are full of deceit and self - gain, and Naruto, being around that, would start to question the ideals he once held. His usually bright and optimistic personality might be clouded with a sense of distrust and a more cut - throat attitude.
His relationship with Sasuke would be very different. Sasuke, who has his own ties to Orochimaru, might see Naruto in a new light. They could either become closer due to their shared connection or more competitive as Sasuke might feel threatened by Naruto's new status. With Sakura, she might be more hesitant around Naruto. She has always seen Naruto as a friend, but the idea of him being related to Orochimaru could make her distrust him at first.
Naruto would likely be more cunning. Since Orochimaru is known for his devious ways, Naruto might inherit some of that. He could be more calculating in battles rather than just relying on brute force. However, he would still have his core of kindness. So, it would be an interesting mix of Orochimaru's slyness and Naruto's big - heartedness.
Naruto's morality could be somewhat skewed. Orochimaru has a very different view on right and wrong compared to Naruto. So, Naruto might start to question some of his previous beliefs. For example, he might be more willing to use dangerous or forbidden jutsus if it means achieving his goals. He'd also probably be more distrustful of others, as Orochimaru always has ulterior motives. This would be a big change from the Naruto who was always so quick to trust and befriend people.