Obviously, Naruto is likely to be one of the main characters. Since it's 'naruto gamer of konoha', he's probably at the center of the story.
In addition to Naruto, there could be some of the older generations in Konoha. For example, Kakashi could play a role. Maybe he acts as a mentor to Naruto in the new gaming - related challenges. Or there could be a new character who is an expert gamer in Konoha that Naruto looks up to and tries to learn from.
Obviously Naruto is one of the main characters as it's related to him. And the Nine - Tailed Fox would also be a central figure considering the title. Also, characters like Sasuke and Sakura are likely to be important as they are Naruto's friends and comrades in the original Naruto series and would surely be involved in the events of the fanfiction.
Most likely Naruto would be one of the main characters. Since it's a Naruto - centered fanfiction, he would be at the heart of the story. There might also be other characters like Sakura, Sasuke, or Kakashi who could be involved in the plot related to the ghosts in Konoha.
Sasuke might also be a main character. In the context of the 'gamer naruto fanfiction', he could be Naruto's rival not just in the normal ninja sense but also in terms of leveling up and gaining power in the 'gamer' system. His actions and development would be important to the overall plot.
Well, Naruto is the main character as it's 'naruto the gamer fanfiction'. But other characters also matter. His rivals like Neji could be part of a competitive aspect in the game world. And characters like Tsunade could be in charge of certain game - like systems, like providing rewards or managing a guild - like structure in the fanfiction. So, it's a mix of the main Naruto characters with their roles adjusted to fit the gamer - themed plot.
Sakura could also be a main character. She's a strong ninja in her own right. In a fanfiction like this, she could be involved in treating the injured when the Hellsing - related chaos starts. Maybe she also tries to understand the unique physiology of Alucard. And Integra from Hellsing. As the head of the Hellsing organization, she could be the one trying to establish some sort of order between the two worlds.
Naruto is likely still one of the main characters. Since it's related to the Naruto universe, he would play a significant role in this fanfiction with his gamer - like adventures.
The main character is Naruto for sure. But in addition to his regular comrades, there could be new characters introduced specifically related to the gamer aspect. For example, there might be a character who acts as a sort of 'game master' in the Naruto world, guiding Naruto in understanding and using his Rinnegan in a game - context. And his friends would still be important, with Sakura perhaps being the one to heal him during his more dangerous 'game - like' battles with the Rinnegan powers, and Kakashi could be a mentor figure in how to combine the Rinnegan and gamer strategies.
Obviously, Naruto in his 'yami' and gamer form is likely to be one of the main characters. There may also be other characters from the Naruto universe like Sasuke or Sakura who could interact with this new Naruto version, either as allies or opponents in the gaming scenarios.
Another character that could be important is Kakashi. As Naruto's mentor, he could play a role in guiding Naruto through the new 'gamer' aspects. For example, he might help Naruto understand how to use his newfound 'gamer' abilities in real ninja battles, or he could give Naruto special 'gamer' - related training missions.
Obviously, Dark Naruto would be one of the main characters. He is the center of this fanfiction concept. Other than him, characters like Sasuke would likely still play important roles. Sasuke might be either an ally or an adversary to Dark Naruto, depending on how the story is written. Also, characters like Kakashi Sensei could be there to try and guide or stop Dark Naruto, given his new, more dangerous state.