One plotline could be their first time attending a neighboring kingdom's festival. They get to experience new cultures, foods, and dances. Anna is excited to try everything while Elsa is a bit more reserved at first. But as the night goes on, Elsa loosens up and they both have a great time, making new friends and memories along the way.
It could be about their first time facing a real threat to their kingdom together. A powerful sorcerer from afar tries to take over. Elsa uses her ice powers to protect, while Anna rallies the people. They have to learn to trust each other's instincts completely. In the end, they defeat the sorcerer and their relationship as sisters and leaders of the kingdom becomes even stronger.
One possible plotline could be that Elsa discovers she's pregnant and has to deal with the newfound powers that might be affected by her pregnancy. For example, her ice powers could become more unpredictable. Another could be Anna's pregnancy journey, where she has to balance her duties in Arendelle with the anticipation of motherhood. She might worry about how to raise a child in a kingdom that has faced so many challenges.
It could be about their first time seeing the autumn leaves change color together. They might be in awe of the reds, yellows, and oranges, and this experience could strengthen their bond as sisters. They could share stories and secrets while walking through the forest filled with the beautiful foliage.
Perhaps the story could revolve around their parents preparing Anna and Elsa for their future roles as rulers. With their parents' alive, they'd have a more traditional upbringing in terms of learning diplomacy and leadership. The family could also be involved in establishing new trade relations or cultural exchanges. And Elsa's powers might be seen as a great asset to be used for the betterment of Arendelle under the watchful eyes of her parents, instead of a feared secret.
One interesting plot could be that Elsa and Anna travel back to the time when their parents first met. They could witness the events that led to their family's formation and perhaps even influence some small details. Another plot might be them traveling to a future where Arendelle is in a post - apocalyptic state due to some magic gone wrong. They then have to figure out how to prevent this future from happening. A third plot could be them traveling to a parallel universe where they have different personalities and powers, and they have to find their way back to their own world while also learning valuable lessons about themselves.
In a fanfiction, Elsa might be killed as a sacrifice. There could be an ancient prophecy that states that in order to save Arendelle from an eternal winter that is a result of an even more ancient curse, Elsa, as the most powerful magic - wielder, has to give up her life. She accepts this fate willingly, and as she dies, her last act is to break the curse, leaving her people in a state of shock and mourning.
Kristoff is often a popular character to include. Since he's Anna's love interest, his presence can add an element of romance and also his skills as an ice - harvester can be useful in different time - travel scenarios. Olaf is another great addition. His naivete and charm can provide some comic relief in tense time - traveling situations. Also, the trolls could be included. They have a lot of knowledge about magic and the past, so they could play a crucial role in guiding Elsa and Anna during their time travels.
To develop their relationship in fanfiction, you could explore their different interests. Anna is more outgoing and loves adventures, while Elsa is more reserved. Have Anna introduce Elsa to new things like a local festival in a neighboring village. At the same time, Elsa can share her knowledge of magic with Anna. Also, create scenarios where they have to communicate better. For instance, if there's a misunderstanding between them caused by a new character in Arendelle, they need to talk it out to resolve it. This would deepen their understanding of each other.
One possible plotline could be that Elsa, with her ice powers, somehow ends up in Peter Parker's world. Maybe she's on the run from some threat in her own realm and Peter, being the friendly neighborhood Spider - Man, decides to help her. They could form a bond as they both have secrets to keep - Elsa with her powers and Peter with his identity as Spider - Man.
There are fanfictions where Elsa and Anna learn new magic together. For example, they might find a long - lost spell book and practice spells that help them better protect their kingdom. It shows their growth as individuals and as sisters.
In some of these fanfictions, Sven could be a significant character. He might help Kristoff in his tasks related to Anna's pregnancy, like carrying supplies. Another character could be the trolls. They are known for their wisdom in the Frozen universe. So they could offer advice to Elsa and Anna about their pregnancies, such as how to deal with any magical complications or how to raise their children to be good and strong. And of course, the people of Arendelle are also important. Their reactions and support play a role in the story.