In the 'naruto neglected by his mother fanfiction', Naruto may have a different approach to his ninja training. Instead of being motivated by the desire to be recognized like in the original story, it could be a way for him to escape from the pain of his mother's neglect. He might train harder and more recklessly, putting himself in danger because he doesn't really care about his own well - being as much, since he feels so unloved at home.
In this type of fanfiction, Naruto could have a different attitude towards authority. As his parents are neglecting him, he might not have that natural respect for figures of power. He may question the village's system more. Also, his dreams of becoming Hokage could take on a new meaning. Instead of just seeking recognition, it could be a way for him to create a family - a village where no one is neglected like he was by his parents.
Well, perhaps in this fanfiction, Naruto is somehow transported to the Batman universe and is neglected by the local heroes at first. He then has to prove himself by using his ninja skills in Gotham's dark alleys, like using his shadow clones to confuse the bad guys and his speed to catch the elusive criminals.
Another aspect could be the relationship between Naruto and his sister. If she is the favored one, she might initially be oblivious to Naruto's pain. But as the story progresses, she could realize how wrong it is and try to make it up to him. This could lead to a complex family dynamic exploration in the fanfiction.
Well, it could be that Naruto is somehow transported to the Green Lantern universe and is neglected by the Green Lantern Corps at first. Maybe they see him as an outsider and don't trust him. But Naruto, with his determination, starts to prove himself by using his ninja skills in a way that the Lanterns eventually come to respect.
In such a fanfiction, perhaps the village's needs are always put first by Naruto, and his sister gets the short end of the stick. For example, he might not be there to protect her when she faces some bullies in the village just because he's too busy with village affairs. This could cause her to doubt Naruto's love for her, and she might even consider leaving the village in search of a place where she feels more valued.
It could be that his sister has some special abilities or talents that the family or the village values more. For example, if she has a very rare and powerful bloodline limit, everyone's attention would be drawn to her. In a ninja world, power and potential are highly regarded, so Naruto might be overlooked because his sister seems to have more of that 'special something' at first glance.
One possible reason could be a misunderstanding. Maybe some false information was spread about his mother, making Naruto believe she had abandoned him. Another reason could be related to the secrecy around his mother. If he grew up feeling alone and not knowing about her, he might develop resentment.
Maybe he's been influenced by someone who has a different view of heritage. For example, if he meets a character who believes that one should create their own identity rather than relying on heritage, Naruto could be swayed. Another possibility is that he has some sort of resentment towards his heritage. Perhaps there are things in his family's past or in the traditions associated with his heritage that he doesn't agree with or is ashamed of.
One possible plot development could be that Naruto's friends in Konoha realize he's missing and start a search mission. They might suspect Kumo immediately due to the history of tensions between the two villages. Meanwhile, in Kumo, Naruto could be held in a secret location. Some in Kumo might want to use him as a bargaining chip against Konoha, while others might see his potential and try to turn him into an asset for Kumo.
A plot for this type of fanfic could revolve around Naruto's inner turmoil. He could be constantly haunted by the question of why his parents neglected him. This could lead him to make some bad decisions, like getting involved with the wrong people. However, through a series of events, he starts to realize that he can create his own family and support system. He then begins to build a new life for himself, one that is not defined by his parents' neglect but by his own strength and the relationships he chooses to cultivate.