Well, in such a fanfiction, it might start with Naruto being in a situation where he becomes Madara's pet. Maybe at first, Naruto is defiant but as time passes, he could start to understand Madara's motives in some strange way. Madara, on the other hand, might initially see Naruto as just a possession but gradually develop a sense of attachment. It could be a really strange and complex relationship that unfolds as the story progresses.
Madara would have to adapt to the different threats in RWBY, mainly the Grimm. In his world, he was used to fighting other shinobi and clans. The Grimm are a whole new type of enemy. However, his Sharingan would give him an advantage in detecting their movements. He might also try to find a way to use the Grimm's negative energy, similar to how he used negative emotions in his own world to fuel his power.
Maybe an orphan from a non - Uchiha clan who has a special ability that Madara finds interesting. This character would be malleable and eager to learn from Madara, as they have no other real family or guidance. They could bring a fresh perspective to Madara's teachings.
The Uchiha clan could be considered the best. They have powerful Sharingan abilities that give them an edge in combat, with the ability to copy techniques and predict movements. Their members are often highly skilled and have great potential.
In fanfiction, Naruto might fear a shinobi for various reasons. One could be that the shinobi has a unique and powerful jutsu that Naruto has never encountered before. For example, a shinobi with the ability to manipulate time could be extremely intimidating to Naruto as it goes against his understanding of combat and the ninja world. This new and unknown power could make him feel vulnerable.
You need to have a clear plot idea first. Then, build interesting characters and their development arcs. Also, create conflicts and resolutions to keep the story engaging.
You might be able to change the name by accessing the settings or profile section within the shinobi story game or platform. Look for options like 'Edit Profile' or 'Change Name'.