Definitely the Northuldra people in general are underrated as a whole for fanfiction. They have a rich culture that we only got a glimpse of in the movie. Focusing on one of the unnamed Northuldra characters, perhaps a young girl who was there when Elsa first arrived in the forest. She could have her own perspective on the events and her own story of how she saw Elsa as a potential savior or a threat. Also, the guards from Arendelle who were with Mattias could be the focus. Their adjustment to living in the forest for so long and their loyalty to Mattias could be explored in a fanfiction.
Kristoff could be a focus too. His life as an ice harvester and his relationship with Sven can add a unique flavor to a fanfiction. Maybe he discovers a hidden ice cave filled with ancient secrets while out on a normal ice - harvesting trip, and he has to decide whether to keep it a secret or share it with the people of Arendelle.
The Wasp. She is a powerful and intelligent character. A fanfiction could center around her leadership skills within the Avengers. Maybe she has to lead the team in a situation where all the big - name heroes are incapacitated. It would show her strategic thinking and her ability to inspire others.
The stable hands who take care of the dragons often get overlooked. They have a unique perspective as they interact closely with the dragons on a daily basis. Fanfiction could explore their lives, their dreams, and how they view the dragon riders.
The White Rabbit is often just seen as the one who leads Alice into Wonderland, but he could be so much more in fanfiction. He could be a time - traveler, for example, and his hurry is because he's always on a tight schedule to different eras. The Tweedle brothers are also underrated. They could be the key to unlocking some ancient secrets of Wonderland. In a fanfiction, they could lead Alice on an adventure full of riddles and puzzles that reveal the true nature of Wonderland. And the Caterpillar is quite an interesting character to focus on. It could be a wise sage who holds the knowledge of the entire Wonderland universe.
Shino Aburame is quite underrated. In a fanfiction, he could be shown as a key figure during the Revolution. His unique insect - based jutsu could be developed further, and his calm and intelligent nature could be used to his advantage in the political and social upheaval of the time.
Hot Pie. He may seem like a minor character, but he has a lot of potential. A fanfiction could explore his life after leaving Arya. Maybe he becomes a famous baker in a large city, and through his bakery, he gets involved in the political intrigues of the city as people from all classes come to his establishment.
Hot Pie is an underrated character. He could be the focus in a fanfiction where his baking skills become more than just a side note. Maybe he bakes special treats that have magical or medicinal properties and gets caught up in the big political and power struggles because of it.
Yes, they probably could. Since it's about their own world, they should be able to understand the basic concepts and stories in the fanfiction.
Another possibility is Gaara before he met Naruto. He had a really tough childhood and was initially very cold - hearted, seeing others as tools or threats. His heart was like a frozen desert, until Naruto's friendship started to thaw it. In this fanfiction, they could explore more of his pre - Naruto state of a frozen heart and how it affected his relationships with others in the shinobi world.
Obviously, Anna herself is a very important character as she is the one who is pregnant. Kristoff would also be important as he is Anna's husband and would be there to support her through the pregnancy. Elsa could also play a crucial role, perhaps using her powers to protect Anna and the unborn child.