In the fanfic, Naruto might obtain Zabuza's sword through a series of events. For example, there could be a situation where Zabuza is incapacitated and Naruto has to take the sword to keep it out of the wrong hands. Or maybe there is a test or trial that Naruto has to pass, and as a reward, he gets Zabuza's sword. Another possibility is that the sword is lost and Naruto finds it, and then has to prove himself worthy of keeping it by facing various challenges related to the sword's history and power.
Maybe he defeated Zabuza in a battle and took it as a trophy.
Maybe he finds it after a battle where Zabuza was defeated. It could have been left behind, and Naruto, seeing its potential, decides to take it up.
One possible consequence could be that Naruto gains a new and powerful weapon. This sword might have unique abilities that could enhance his combat skills. He could use it to intimidate his enemies or as a last - resort weapon when his regular jutsu are ineffective.
Well, perhaps Naruto takes Zabuza's sword and it becomes a symbol of his growth. He may face challenges from those who think he's unworthy of possessing such a weapon. Also, he could modify the sword to better suit his fighting style, like adding some of his own chakra -infused elements to it.
A minor character like a blacksmith's apprentice could find Zabuza's sword. Instead of using it for fighting, they study it closely. They discover a unique metal alloy in the sword that they use to create new and improved weapons for their village. This not only changes their own fate as they become a renowned blacksmith, but also the fate of the village as they now have better weapons to defend themselves.
Well, he might obtain it in a fight. Maybe after defeating an enemy who had stolen Zabuza's sword from its original place. Or perhaps he discovers it in an old, forgotten hideout where Zabuza once stashed his things.
Well, another place could be Naruto - related forums. There are often threads where fans share and discuss their favorite fanfics. Some might be specifically about Zabuza's sword. You can join in the conversation and ask for recommendations too.
Some of his friends might be worried at first. They know Zabuza was a dangerous enemy before. But Naruto could convince them that he'll use the sword for good.
Good writing style also matters. The descriptions of the sword, like its appearance and the way it cuts through things, should be vivid. If the author can make you feel like you're right there in the Naruto universe, watching the sword in action, then it's a great fanfic. Also, it could explore the backstory of the sword in more detail than what was shown in the original series, which would make it really engaging for fans.
Another plot could be that Zabuza's sword ends up in the hands of an enemy of Konoha. Konoha sends a team of ninjas, including some of the younger generation like Naruto and his friends, to retrieve it. Along the way, they learn about Zabuza's legacy and the true strength of the sword. They have to battle the enemy who has already started to unlock some of the sword's powers, but in the end, they manage to get it back and decide what to do with such a dangerous weapon.
Well, in some fanfictions, Naruto might defeat Kisame in a battle and take the sword as a trophy. Maybe he uses his newfound Sage Mode powers or some other advanced jutsu to overpower Kisame and claim the sword.