Well, in terms of plot changes, Naruto's upbringing would be different. Instead of being raised as a ninja in the Hidden Leaf, he might be exposed to the ways of the Soul Reapers from an early age. This could lead to a whole new set of training regimes and challenges. His goals might also change. Instead of aiming to become Hokage, he could be more focused on matters in the Soul Society. And his interactions with the original Naruto characters would be altered. For instance, Sasuke might view him differently because of his new heritage. Plus, there could be a whole new set of villains related to the Bleach universe that he has to face.
One possible plot change could be Naruto having different abilities. Since Shunsui Kyoraku has unique powers in Bleach, Naruto might inherit some of those. For example, he could have a zanpakuto - like ability in addition to his ninja skills. Another change could be in his relationships. His connection to the Bleach universe through Shunsui might introduce new characters into his life, like other Soul Reapers. Also, his backstory would be completely different, perhaps involving the Soul Society instead of just the Hidden Leaf Village.
It depends on the specific fanfiction. Fanfictions are known for their creativity and bending of established rules. While Naruto is a shinobi from the Hidden Leaf Village in his own series and Shunsui Kyoraku is a captain in Bleach, in the world of fan - made stories, the author may have crafted a complex and unique narrative where Naruto is indeed the son of Shunsui Kyoraku. Maybe there's some sort of magical or time - traveling element involved to make this seemingly odd connection work.
Well, it could be that Naruto, as Merlin's son, has hidden magical powers that he discovers gradually. Maybe he uses these powers in the Naruto universe to fight stronger enemies or to bring peace in a different way. For example, his magic could be combined with his ninja skills.
One possible plot twist could be that Naruto's primordial powers are sealed away by an unknown force, and he has to go on a journey to unlock them. Another could be that his friends turn against him when they discover his true nature as the son of a primordial being, fearing his power.
One possible plot twist could be that Naruto has hidden Uchiha abilities that no one expected. This could change the power balance in battles. Another could be that his relation to Izuna causes conflict within the Uchiha clan who are not sure how to deal with this unexpected heir.
Perhaps the plot could involve Naruto being in a world where the son of a goddess has some sort of power or status that makes Naruto oppose him. Maybe the son of the goddess is causing trouble in the ninja world, and Naruto, with his sense of justice, stands against him.
A possible plot could be that in a strange twist of fate, Frieza discovers a way to have a child with a human - like being from Naruto's world. Naruto is born as this hybrid son. Frieza wants to use Naruto to conquer both worlds, but Naruto rebels against his father's evil plans. He teams up with his friends from the Naruto universe and some of the good - hearted characters from Frieza's world (if there are any) to stop Frieza and bring peace to both universes. Along the way, Naruto has to learn to control his unique powers which are a blend of ninja skills and Frieza's alien abilities.
One possible consequence is new and unexpected abilities. For instance, if his DNA is changed to incorporate some sort of spirit energy, he could gain the ability to communicate with the dead. Another consequence could be changes in his appearance, like his hair color or eye color changing. This can also lead to social isolation as his friends might not recognize him at first.
In the fanfiction, Naruto could enter Kaguya's mind. He might discover her past traumas that led her to become so power - hungry and vengeful. By understanding her pain, Naruto could offer her forgiveness and a new path. He could show her a vision of a future where she is part of a united world, not feared or hated, but respected and loved if she changes her ways. This could be a powerful incentive for Kaguya to change.
One possible plot twist could be Naruto struggling with the dark reputation associated with Orochimaru. Since Orochimaru is known for his unethical experiments and evil deeds, Naruto might face distrust from the village. Another twist could be that Naruto has an inborn talent for snake - related jutsus due to his supposed father. This could lead to a whole new set of training and challenges as he tries to master these unique abilities while also dealing with the moral implications of using Orochimaru - inspired techniques.
The plot could also explore how Naruto's identity as Nagato's son affects the Akatsuki. Maybe some members of the Akatsuki would try to recruit him or use him for their own purposes. On the other hand, Naruto might try to reform the Akatsuki from within. His connection to Nagato could also lead to a different resolution of the conflict between the ninja villages. Instead of just uniting the villages as in the original story, he could aim to create a more global peace based on Nagato's broader view of the world, which was not just limited to the ninja villages.