Anna, being outgoing and adventurous, would probably get along great with Chat Noir. They could have a lot of fun banter and adventures together. When it comes to Elsa and Hawk Moth, Elsa's coldness (in personality as well as power) would be a contrast to Hawk Moth's manipulative and power - hungry nature. She would be very resistant to his attempts to use her for his evil plans.
Obviously, Ladybug and Chat Noir are the heroes in the Miraculous world, so they would be main characters. In Frozen, Elsa and Anna are the key figures. However, we might also see other characters like Tikki and Plagg from Miraculous having some interactions with the Frozen characters. For example, Tikki might be fascinated by Elsa's ice powers and try to understand how they work compared to the Miraculous powers.
Spiderman would likely be initially cautious when meeting Ladybug. He's used to operating on his own in New York, and suddenly meeting a hero from Paris with a very different power set would be a bit of a shock. He might be impressed by her ability to create objects with her yo - yo and use them in combat.
In fanfiction, the Miraculous Ladybug characters could interact with the UN in multiple ways. First, they could be invited to give a presentation on the nature of akumas and how they've been combating them. Then, they might be part of a task force created by the UN to deal with a global akuma - like threat. Ladybug would use her leadership skills, while Chat Noir would bring his charm and combat skills. They would also interact with UN staff, learning about international laws and regulations regarding superhero activities. And perhaps they would even help in training other heroes from around the world who are brought together by the UN.
Well, Peter Parker might be really curious about Ladybug's powers. He'd probably ask her a lot of questions about how her Miraculous works. Ladybug, on the other hand, would be interested in Spider - Man's scientific gadgets. They could exchange knowledge and techniques.
Ladybug might be in awe of Captain America's leadership and sense of justice. She could learn a lot from him about leading a team. Meanwhile, Cat Noir would probably be intrigued by Iron Man's high - tech gadgets and try to get his hands on some. He might even joke around with Thor, comparing their 'cat - like' reflexes.
When it comes to how the characters' personalities change in this crossover, it's quite complex. Marinette, as Ladybug, may start to show a more vulnerable side. The beauty and danger of the Swan Lake world make her realize that she can't always be in control. Chat Noir might become more solemn. The grandeur and the dark undertones of Swan Lake could make him more aware of the seriousness of their situation. And for other characters like Chloe, she could either be completely out of her depth and become more submissive or, in a twist, she could try to take on the role of a villain within the Swan Lake story, using her mean - girl tactics in a different, more magical context.
Marinette is shy and often nervous, while Alya is bold and outgoing. Their personalities can create a great dynamic. Alya can encourage Marinette to be more confident and take risks. For example, when Marinette is hesitant to enter a fashion competition, Alya pushes her to do it.
Ladybug's power of creation with the Lucky Charm could be enhanced by Spiderman's scientific knowledge. He might be able to analyze the Lucky Charm and figure out new ways to use it. For example, if the Lucky Charm is a simple object like a key, Spiderman could use his knowledge to turn it into a tool to unlock a special device that helps them in their fight.
They might start off as rivals. Bridgette, being a positive and helpful character, could see Felix as a bit of a troublemaker at first. But as the story progresses, they find common ground in their understanding of the Miraculous world and start to work together.
One possible plot could be that Ladybug and Chat Noir are transported to the world of Frozen. There, they meet Elsa and Anna. Maybe they team up to fight a new villain that is causing chaos in both the Miraculous and Frozen universes. For example, a villain might be using the power of the Miraculous to freeze parts of Paris and also trying to take over Arendelle.