Perhaps the male OC is a mysterious figure who appears to Moana in her dreams before she even sets out on her journey. He seems to know a great deal about the heart of Te Fiti and the approaching darkness. When they finally meet in person, he reveals that he has a connection to an ancient power that can either help or hinder Moana's mission, and she has to figure out how to work with him.
One idea could be an OC who is a long - lost relative of Moana. This OC could have been separated from the family during a great storm years ago. They could have unique skills, like being able to communicate with a different type of sea creature that Moana has never encountered. This would bring new adventures as Moana and the OC try to figure out how this new discovery could help their island.
Maybe the OC is from a different island and Keoni helps her adjust to life on Moana's island. Along the way, they fall in love. There could be cultural clashes and misunderstandings at first, but as they get to know each other better, they bridge the gaps between their two cultures.
First, decide on his backstory. Where is he from? What kind of family does he have? For example, if he's from a fishing village, his skills and values might be centered around the sea. Then, think about his personality traits. Is he brave like Moana or more cautious? If he's more cautious, it could create interesting conflict as Moana is often bold in her actions. Also, consider his appearance. Does he have a distinct look, like a unique tattoo or a special piece of clothing that represents his heritage?
One idea could be that Moana discovers a hidden part of the ocean that has a special connection to her ancestors. The ocean could lead her there, and she might find ancient artifacts or powers that help her protect the island in a new way.
One idea could be a Moana crossover with Frozen. Moana could end up in Arendelle due to a magical storm. She teams up with Elsa and Anna to stop an approaching iceberg that is threatening both her island and Arendelle. Moana's skills in sailing and her connection with the ocean could be combined with Elsa's ice powers to find a solution.
One common theme is adventure. Since Moana's story is about her journey across the ocean, many OC characters are inserted into this adventure. They might face the same challenges as Moana, like the angry sea or the monsters. Another theme is friendship. The OC often forms a strong bond with Moana, helping each other grow and learn.
Another concept could be a crossover where some of Naruto's friends like Sasuke or Sakura also end up in Moana's world. They all form a team with Moana and her friends to fight against a dark force that is trying to take over the ocean and the land.
One idea could be that they go on adventures together to explore new islands. Maui could use his strength and Moana her navigation skills.
One idea could be a story about Moana's journey during her pregnancy. It could focus on how she still tries to maintain her connection with the ocean and her village. Maybe she teaches the children about the importance of nature even while she's expecting.
In this fanfic, Moana is on a new voyage and gets lost in a mysterious part of the ocean. She ends up near Ariel's territory. Ariel, who has always been interested in humans, approaches Moana. At first, Moana is a bit startled by a mermaid but soon realizes they share a common love for the ocean. They start to exchange knowledge. Ariel shows Moana some of the amazing underwater wonders she has never seen before, and Moana teaches Ariel about the stars that help her navigate. Together, they face a sea monster that is causing trouble in both their areas of the ocean.