Sakura and Sasuke are very likely allies. Sakura has her medical skills and combat abilities, and Sasuke, despite his past issues, has great power. They've been comrades with Naruto for a long time.
I think Gaara could be an ally. He has his own powerful sand abilities and he has a connection with Naruto. They understand each other on a certain level. Also, the other Konoha ninjas like Neji and Lee might join in. Neji has his Byakugan and Lee has his incredible taijutsu skills. All of them together could form a formidable force against the Akatsuki.
Sasuke could potentially be an ally. Even though they have their differences, in the Akatsuki setting, they might realize they need to work together. Another could be Itachi. Itachi has his own motives and might see Naruto as a key to achieving certain goals within the Akatsuki. Also, Konan could be an ally. She seems to be more open - minded compared to some of the other members and might be swayed by Naruto's positive attitude.
Sakura would definitely be one of his allies. She's always been by Naruto's side, and in this fanfiction, she could help him with his disguises, like using her medical ninjutsu to create more realistic physical changes. Kakashi could also be an ally. His intelligence and experience would be valuable in planning Naruto's undercover missions. He could teach Naruto how to act more convincingly in different disguises.
I think Gaara could be an ally. Gaara has control over sand and is very powerful. He and Naruto have a mutual respect for each other. Additionally, Jiraiya. Jiraiya was Naruto's mentor and has a vast knowledge of different jutsu and combat techniques that could be used against Omega Shenron.
I think Hinata could be an ally. She has always been in love with Naruto and would not stand by while he is in danger from Dark Naruto. Additionally, Shikamaru is smart and strategic. He might see the threat of Dark Naruto to the village and decide to assist Naruto, using his intelligence to come up with battle plans.
Sasuke would be a likely ally. They have a long - standing relationship and have fought side by side before. Sasuke's Sharingan and his own unique abilities would be a great asset against the Ten - Tails.
Itachi could be a likely candidate. He has always had a complex relationship with Naruto. He knows Naruto's potential and his importance in Sasuke's life. Itachi might see Naruto as a key to changing the Akatsuki from within. He could approach Naruto with his calm and mysterious demeanor, explaining to him the real goals of the Akatsuki that are hidden beneath their violent exterior.
Well, it could start with Naruto getting some crucial information about the Akatsuki's next move. So he embarks on this hunt. Along the way, he could face moral dilemmas, like whether to spare some Akatsuki members who might have a sad backstory. He also has to deal with the fact that the Akatsuki are very powerful and cunning, and he has to constantly outwit them.
Pein could be another one. As the leader of the Akatsuki, he might see baby Naruto as a means to an end. He could either want to use Naruto for his own grand plans or, in a more interesting twist, be swayed by Naruto's innocence and change his perspective on the Akatsuki's goals.
Well, first of all, Jiraiya might return in some form, like a spirit guide or something, and be an ally to Naruto. Tsunade would also be there, using her leadership and medical ninjutsu. And then there are the new generation characters like Boruto. He could learn from Naruto and help out, seeing as he also has his own unique abilities. The Allied Shinobi Forces from the previous big battles might also reunite to support Naruto in saving the world.
Itachi and Kisame could be a pair with a close bond. Itachi is a very reserved person, but Kisame seems to respect and understand him to some extent. They often work together on missions, and this could be seen as a form of 'family' bond within the Akatsuki. Another possibility is Deidara and Sasori. Despite their differences in art forms, they seem to have a connection. Deidara looks up to Sasori in some ways, like a younger brother might look up to an older one.