It could also be a completely new character introduced into the fanfiction. A foreign ninja who was inspired by some of Danzo's ideas (not the bad ones) and comes to Konoha to take on the role of successor, bringing in new perspectives and ways of doing things.
Well, it really depends on how the fanfic is written. If the fanfic focuses on Naruto's weaknesses and Danzo's preparedness, Danzo could potentially win. He has a lot of political power and experience. However, if it follows the general power scale of the Naruto universe, Naruto has a better chance. His positive energy and the power of friendship (a bit cheesy but true in Naruto's world) often help him overcome his opponents. Naruto also has the ability to quickly adapt to new situations, which would be a big plus against Danzo.
He'll likely lose his power and influence in the village. Once Naruto reveals his secrets, the villagers won't trust him anymore. His actions might be put on trial, and he could be exiled from the village.
It could also be due to Naruto's outcast status in the village initially. Danzo might think that banishing Naruto would be an easy decision as Naruto doesn't have many supporters at first. He might believe that by getting rid of Naruto, he can maintain the status quo in the village and prevent any disruptions that Naruto's presence might cause in the future.
If we consider a Naruto - Danzo fight in a fanfiction, Naruto has several factors in his favor. His training with Jiraiya and other experiences have made him a formidable ninja. He can go into Sage Mode, which enhances his physical abilities and gives him access to more powerful jutsu. Danzo, while being a shrewd and experienced ninja, has his weaknesses. His over - reliance on the Sharingan and his somewhat underhanded methods might not be enough against Naruto's raw power and unwavering spirit.
Most likely Danzo would be seen as the main antagonist. His actions throughout the Naruto series were often self - serving and harmful to others, like his role in the Uchiha massacre. So when Naruto talks to him, he would be the one Naruto has to oppose or at least try to change.
Sure. The characters are a huge part of Naruto Shippuden fanfiction. Fanfic writers use the characters to attract readers who are fans of those characters. They might focus on a character's backstory that wasn't fully explored in the anime and expand on it. Also, the interactions between characters in the original show give fanfic writers ideas for different scenarios in their stories.
By their unique abilities. Naruto's Rasengan, Sasuke's Sharingan, these abilities can be the starting point for many fanfiction ideas. Writers can think about how these abilities could be used in different battles or situations not shown in the original.
One of the most popular is 'Naruto Shippuden: Sakura Hiden - Thoughts of Love, Riding Upon a Spring Breeze'. It's popular because it shows Sakura in a new light, with her own adventures and growth.
Naruto is obviously the most important. Sasuke is also crucial as his relationship with Naruto drives a lot of the story. Kakashi is Naruto's mentor. Sakura is Naruto's teammate and she has her own growth arc. Then there are villains like Madara and Obito. Also, characters like Jiraiya who plays a big role in Naruto's training and development are important in the Naruto Shippuden life story.