A really interesting plot could involve an Otsutsuki OC who gets stranded on a planet with a completely different culture and technology level. They have to adapt and survive while also trying to find a way back home. Along the way, they form an unlikely alliance with the natives of the planet, and together they discover secrets about the Otsutsuki that could change the fate of both the OC's clan and the new planet they are on.
One idea could be an Otsutsuki OC who comes to Earth not for conquest but to study the unique life forms here. They could befriend some of the local ninjas and learn about the concept of friendship, which is alien to the Otsutsuki. This would lead to a series of adventures where they have to protect their new friends from other more hostile Otsutsuki members.
Perhaps an Otsutsuki OC who has a special power that sets them apart from the rest of their clan. For example, the ability to heal instead of destroy. This OC could then be on a mission to change the Otsutsuki's ways from a distance, using their influence on other worlds. They might face challenges from within their own clan who see their ideas as a threat to their traditional ways.
One idea could be to cross Hagoromo Otsutsuki with a character from a different anime universe, like Goku from Dragon Ball. They could have a power - level comparison and then team up against a common enemy. Another plot could involve Hagoromo in a modern - day world crossover, where he has to adapt to new technology while still using his ancient powers.
One idea could be Indra Otsutsuki crossing over into a modern-day world. He could struggle to adapt to the new technology and social norms while still having his powerful ninja abilities. Maybe he meets a group of people who initially fear him but then come to understand his situation and help him navigate this strange new world.
One idea could be a story where a young ninja discovers they have a hidden Otsutsuki bloodline power that gives them the ability to control gravity. This power sets them apart from their peers and makes them a target for both those who want to use their power and those who fear it.
One idea could be a crossover where Naruto's Otsutsuki powers somehow connect with the supernatural elements in DxD. For example, his ability to absorb and use chakra could be related to the magic in DxD. Maybe he could use his Otsutsuki powers to enhance the abilities of the devils or angels he meets in the DxD world.
One idea could be a story where an Otsutsuki member infiltrates the Akatsuki. They could have their own secret motives that conflict with the Akatsuki's goals, like using the Akatsuki as a tool to gather more chakra for their own clan's needs. Another plot could be about a young Naruto being mentored by an Otsutsuki in secret, and how this affects his relationship with the Akatsuki later on. Maybe he tries to persuade them to change their ways using the knowledge he got from the Otsutsuki.
One interesting idea could be exploring the unique powers that the otsutsuki clan brings into the Naruto universe. For example, how their god - like abilities might change the power dynamics among the existing ninja clans. Another idea could be the relationships between Naruto and otsutsuki characters. Maybe Naruto has to learn from them to gain new skills for protecting his village.
One idea could be an otsutsuki crossover with the Naruto universe. Imagine an otsutsuki character interacting with Naruto and his friends, perhaps teaching them some of their unique jutsu or having a power struggle. Another idea is an otsutsuki crossover with a different anime like One Piece. The otsutsuki's otherworldly powers could create chaos in the Grand Line.
Maybe a fanfiction where Kaguya is reborn in a different form and Naruto is the only one who can sense her true identity. They form an unlikely alliance to fight a new common enemy that threatens both the ninja world and the secrets Kaguya holds.
One interesting plot idea could be Kimimaro Otsutsuki being sent on a secret mission to a far - off planet. He has to face various unknown enemies and strange terrains. Along the way, he discovers a new form of chakra that he has to master in order to complete his mission.
Another plot could revolve around an OC who is a Spartan trainee that doesn't quite fit the mold. They have a different way of thinking and approaching combat. In Halo 4, they end up being the key to solving a mystery related to the Prometheans. Maybe they find a way to communicate with the Prometheans and convince some of them to stop fighting the humans.