Well, it could change in many ways. Maybe in the new timeline, Killua goes back and is able to protect Gon from some harm that he couldn't in the original timeline. This act of protection could make Gon see Killua in a new light, as an even more reliable friend. On the other hand, Killua might also be too overprotective, which could cause some friction in their relationship as Gon is a very independent character.
If Killua goes back in time, his relationship with Gon could become stronger. He might use his knowledge of their future together to avoid any misunderstandings that happened before. For example, he could be more open about his feelings and fears earlier, which would deepen their bond.
When Killua goes back in time, his relationship with Gon may face challenges. He has the knowledge of what will happen in the future, but Gon doesn't. Killua might try to change things in a way that Gon doesn't understand at first. For instance, Killua could try to prevent Gon from going on a certain adventure because he knows it will be dangerous. But Gon, being the adventurous type, might see this as Killua trying to hold him back. However, as time goes on and Gon realizes Killua's intentions, their relationship could grow into a more mature and trusting one.
If Ron goes back in time, he might have a chance to see Hermione in a new light. Maybe he realizes her importance earlier and becomes more protective of her from the start. This could lead to a more mature and deeper relationship developing faster than in the original timeline.
Anakin's time travel could lead to a completely different relationship with Padmé. He may realize that his obsession with her in the original timeline was part of what led him down the dark path. So, instead of repeating the same pattern, he could focus on being her friend and protector in a more platonic way. This new dynamic might not only change their relationship but also have a significant impact on Anakin's overall character development and his place in the galaxy.
Harry might be more protective of his friends in the new timeline. He has seen what can happen to them in the future, so he'll do everything he can to keep them safe. With Hermione, he could encourage her to pursue her interests more freely, knowing how important her knowledge and skills will be. And with Ron, he may try to boost his confidence from the start, so Ron doesn't feel overshadowed as he did in the original timeline.
Often, they show a deeper level of commitment. The mpreg forces them to rely on each other more. For example, Gon might become more protective of Killua during the pregnancy.
Gon in fanfiction can be very single - minded in his pursuit of goals, just like in the original. He might be a bit more naive at times, which can lead to interesting plot twists. Killua is often portrayed as having a complex emotional side. He struggles with his past as an assassin and his loyalty to Gon. His cool exterior may crack in some fanfictions, showing his true feelings.
If Thor goes back in time, his relationship with Loki would be very different. In the past, Loki might not be as bitter and jealous as he becomes in the future. Thor could try to be a better brother and prevent Loki from feeling left out, which would change their entire dynamic. With his friends like the Warriors Three, he might be more protective of them in the past, knowing the challenges they will face in the future.
When they go back in time, they may encounter situations where they have to protect each other. This could be a big turning point in their relationship. Let's say they go back to a time when there were dark wizards targeting their families. They would have to put aside their differences and fight side by side. This could lead to a complete transformation of their relationship. Draco might realize that Harry is not his enemy and Harry could see that Draco is capable of loyalty and self - sacrifice. It would be a very different dynamic from their relationship in the original timeline.
Since Naruto has more knowledge of the future, Kakashi might start to rely on him more, which could shift their relationship. Naruto could also see a different side of Kakashi from the past, and this new understanding could deepen their connection. For example, they might have to face some challenges together that make them trust each other more than before.
His Force abilities could be different. Maybe he would discover new aspects of the Force in the past that were lost in his original time. For example, he could learn ancient Force techniques that were forgotten over time.
Well, if Draco goes back in time, he might become more humble. Seeing the past and the mistakes his family has made or is about to make could make him less arrogant. He would realize that his pure - blood status doesn't give him the right to look down on others.