If Bell goes to the past and meets Carsile, it could also create a ripple effect. Their meeting might not only change their individual stories but also the stories of those around them. For example, Carsile might introduce Bell to other vampires, and Bell's presence could cause friction or cooperation among them. This could lead to new alliances or rivalries, which would completely reshape the original storyline. Also, Bell's actions in the past could have unforeseen consequences that spread throughout the entire world of the story, from the vampire side to the human side.
The plot could be that Bell is sent to the past to observe Carsile for some unknown reason. As Bell follows Carsile around, they start to interact more. Carsile may initially be suspicious of Bell but then realizes that Bell has no ill intent. Their relationship could develop into a friendship or something more, all while they are navigating the complex world of vampires in the past, with different vampire clans and their own rules.
Maybe in the fanfic, Bella goes to the past and meets Carlisle when he is still struggling with his new - found vampire nature. She could offer him a different perspective on being a vampire, perhaps a more human - centered view. This could lead to a deep connection between them and change the way Carlisle interacts with other vampires in the future. It could also lead to a different relationship between Bella and the Cullen family when she returns to her own time.
I'm not sure of a specific 'bella goes to past meets carsile fanfic' off the top of my head. But you can try searching on fanfic websites like Archive of Our Own. There are often tags and search functions that can help you find stories with those specific elements.
The meeting could also have an impact on Naruto's relationship with his village. If future Naruto shares with past Naruto how important it is to have the trust and support of the village in the long run, past Naruto might focus more on building bridges within Konoha. This could lead to a more united village earlier in the story and change the way they face external threats.
The storyline would change significantly. Firstly, Lelouch would have the upper hand in terms of knowledge. He'd know who to trust and who not to trust right away. This would change the power dynamics in his relationships. For instance, he could expose the true nature of some of the Britannian nobles much earlier.
It could potentially change the whole direction of the series. If past Kratos gets advice from his future self, he might make different choices in his battles. For instance, in a fight against a certain god, he could use a different strategy that future Kratos has taught him.
It could change it a great deal. Goku might learn more about his Saiyan roots earlier, which could potentially make him more in tune with his Saiyan side. This could lead to him training differently or having different goals. For example, he might be more interested in exploring his Saiyan heritage and what it means for his power - up potential.
A 1930s 'Game of Thrones' fanfic would transform the storyline in multiple ways. Firstly, the role of women would be different. In the 1930s, there were women starting to break out of traditional roles. So, female characters in 'Game of Thrones' like Arya or Sansa might have more opportunities to be independent and fight for their own causes. Secondly, the concept of war would change. With the new military technologies of the 1930s, battles would be more mechanized. This would also affect how different houses strategize and fight for power. Also, the religious aspect would be different. The old gods and the new god might be less relevant, and new ideologies might emerge as a replacement, much like how new political and social ideologies emerged in the 1930s real - world.
In the fanfiction, Natsu and Erza's meeting could be a catalyst for a new arc in the Fairy Tail story. Suppose they discover a hidden threat to the guild during one of their interactions. This could lead to a whole new adventure where they have to gather the other guild members and use their combined skills to defeat the threat. It would be a story full of action, friendship, and magic.
The storyline would change drastically. Instead of following the path of protecting Konoha, Naruto would be involved in Akatsuki's missions. These missions are often related to capturing tailed beasts, which is the opposite of what he has been doing. So, there would be a complete reversal of his goals.