Well, I've come across some. Some fanfics focus on how Jack Frost, with his icy powers, and Rapunzel, with her long hair, meet in a magical forest. Their different natures create an interesting dynamic. In these stories, they often have to overcome obstacles like an evil sorcerer who wants to keep them apart to fully embrace their love.
One interesting fanfiction could be where Jack Frost accidentally freezes Rapunzel's long hair and then has to find a way to thaw it without causing her harm. Another might be a story where they meet in a magical forest during a solstice event and team up to defeat an evil sorcerer who is threatening both their worlds.
The Jack Frost, Elsa and Rapunzel love story could start with a wintery adventure. Jack Frost, who is used to roaming the world alone during winter, stumbles upon Elsa's ice kingdom. He is fascinated by her. At the same time, Rapunzel, who has always been curious about the outside world, also finds her way there. Elsa might initially be a bit guarded, but Jack Frost's carefree nature breaks the ice (no pun intended). Rapunzel's sunny personality then melts their hearts further. They could start by sharing their stories, like how Jack Frost came to be, Elsa's past with her sister and Rapunzel's life in the tower. As time passes, their friendship could turn into a deep and loving relationship where they support each other through any difficulties that come their way, whether it's an ice - related disaster or a problem caused by Rapunzel's long hair getting tangled in something.
A possible plotline could be that Jack Frost is on a mission in Rapunzel's world and accidentally stumbles upon her tower. They form an instant connection. As their relationship progresses, Rapunzel gets pregnant. Now, they need to figure out how to raise the child. Jack Frost wants to introduce the child to his icy world, but Rapunzel is worried about the cold environment. Meanwhile, there could be a villain, like an evil witch or a jealous magical being, who wants to harm Rapunzel and the baby. So they have to rely on their combined powers and the help of their friends from both their worlds to protect their family - to - be.
Fanfiction.net is also a great place to search. It has been around for a long time and has a vast number of user - generated stories. Just type in 'Jack Frost and Rapunzel' in the search bar and you'll get a list of relevant fanfictions. However, the quality may vary, so you might need to read a few summaries or reviews if available to find the good ones.
It would be a very fantastical love story. Jack Frost would use his frost to create beautiful designs around Elsa's ice castle, and Rapunzel would be in awe of their powers. They would probably have picnics on ice - covered meadows with Rapunzel bringing delicious food from her tower. And at night, Jack Frost would make the stars shine brighter while Elsa would create an ice - skating rink for them to have fun on.
Well, in a 'jack frost x merida fanfic', the settings can also be quite diverse. It could be set in a wintry landscape that Jack Frost is familiar with, or in the Scottish highlands where Merida hails from. The story might revolve around Jack Frost teaching Merida some of his ice - related magic, or Merida showing Jack Frost how to be more in touch with his emotions. There are so many possibilities for character development, plot twists, and world - building in such a fanfic.
There's also 'The Meeting of Jack and Rapunzel'. In this fanfic, their first encounter is so well - written. It shows how their personalities clash at first but then gradually they start to understand and care for each other. It's a heartwarming read that really develops their relationship over time.
You can try Archive of Our Own (AO3). It has a vast collection of fanfics, and you're likely to find a good number of 'jack x rapunzel' ones there. Just use the search function and type in the relevant tags.