It could also change his offensive style. Naruto might be able to channel his chakra through the armor to create more powerful rasengan variations. The black lightning could add an extra element of destruction to his attacks.
In some fanfictions, the Lightning Armor might have unique side effects. It could potentially drain a character's chakra at a rapid rate if not properly controlled. This adds an element of risk to using it in combat.
Naruto himself is often associated with it. Since he is the main character of the series, many fanfictions explore his potential with the Lightning Armor. He might learn to use it in unique ways, like combining it with his Rasengan.
One possible plot twist could be that Naruto has a really hard time controlling the Lightning Armor at first. Instead of it enhancing his speed and power, it causes him to accidentally electrocute his friends. This would create a lot of tension and drama as he has to figure out how to master it without hurting those around him.
One popular 'lightning armor naruto fanfic' might be 'Naruto: Lightning's Edge'. In this fanfic, Naruto discovers a new power related to lightning armor which gives him enhanced speed and strength. It often features exciting battles against powerful foes.
One idea could be Naruto discovers an ancient scroll that details the secrets of the black lightning armor and he has to train in isolation to master it. This could lead to him developing new techniques related to the armor.
His relationship with Sasuke might become more competitive. Sasuke, seeing Naruto learn such a powerful technique, would strive to become stronger too. This could lead to more intense sparring sessions between them and a bit of friendly rivalry.
In a fanfiction about Naruto's Lightning Release, there could be a story where a young girl discovers she has latent Lightning Release abilities. She trains hard under Kakashi to master it. Along the way, she befriends other ninjas and together they form a team. Their adventures involve using Lightning Release to solve mysteries and defeat enemies. For example, they might use Lightning Release to track down a missing-nin who has a special ability to hide from normal detection methods.
One idea could be that Naruto discovers an ancient relic that transforms into knight armor. This armor could enhance his abilities, like making his Rasengan even more powerful. It might also change his appearance, giving him a more chivalrous look. He could then use the armor's special features, such as enhanced speed or defense, in battles against powerful enemies.