Some characters could be guardian spirits. They would subtly influence the living by guiding them away from danger or towards positive decisions. This interaction would be more of an invisible force that the living might not be fully aware of.
They might communicate through dreams. In many beliefs, the dead can visit the living in their dreams to convey messages or give warnings.
The ponies' magic could play a big role in their interactions. If a dinosaur was about to attack, a unicorn pony could use a protection spell. The Jurassic World characters, especially the park rangers, might see the ponies as potential allies in controlling the dinosaurs. And the ponies could learn a lot about survival in a harsh environment from the humans.
Perhaps it would explore the concept of reincarnation. The story could follow the character as they are reborn into a new life, with faint memories of their past life. It might show how their experiences in the previous life shape their new existence, and how they gradually come to realize their connection to their former self.
Their interactions could also be based on their combat styles. Naruto's flashy and powerful ninjutsu would contrast with Kid's more calculated and precise attacks. In a battle together, they would have to find a way to combine their styles. Naruto might be the one to rush in first, and Kid would follow up with his precise strikes. And outside of battle, they could bond over their shared goal of protecting their respective worlds or the people they care about.
Superman and All Might would probably have a great deal of respect for each other. They are both symbols of hope in their respective universes. All Might might be a bit in awe of Superman's natural powers, while Superman would admire All Might's determination despite having a quirk that was slowly fading. They could exchange stories about their battles and how they inspire others.
The heroes in My Hero Academia would be in awe of Spider - Man's abilities. His ability to climb walls and swing from buildings would be something new to them. They might try to incorporate some of his moves into their own fighting styles. Midoriya would look up to Spider - Man as another symbol of hope, just like All Might.
The soldier might be a bit rough around the edges at first. He could be used to a more serious and tough environment. But the ponies, with their friendly and kind nature, would probably try to make him feel welcome. For example, Twilight Sparkle might offer to show him the library and share knowledge, while Pinkie Pie would throw a party to cheer him up.
The interaction could be really complex. The ponies, being magical creatures, could try to use their spells to understand Godzilla's language or intentions. Godzilla, who is used to a world of destruction and chaos, might be confused by the colorful and peaceful world of Equestria. There could be a lot of misunderstandings at first. For example, when Godzilla roars, the ponies might think he's angry, but he could just be trying to communicate. And as they slowly start to understand each other, they could form an unlikely alliance. Maybe the ponies help Godzilla find his way home, and in return, Godzilla protects them from any future threats that might come from his world.
Start by identifying your values. What do you truly care about? Once you know that, make decisions based on those values. For instance, if family is important to you, allocate more time for them.
In a 'living with dragon' fanfiction, Neville could find a way to use his knowledge of plants to feed the dragon. He might discover certain magical plants that are a dragon's favorite. Ginny would be fearless and would probably be the first to try and train the dragon to do tricks. The Weasley twins would surely come up with some inventions to make living with the dragon more fun or easier. The dragon would also interact with the Hogwarts ghosts. Peeves might play tricks on the dragon, while the Fat Friar would try to keep the peace between them.
Batman would likely be very suspicious of Light Yagami. Light sees himself as a kind of 'god' when he has the Death Note, but Batman, who is all about justice in a more traditional sense, would not tolerate Light's actions. He would probably try to stop Light from using the Death Note. As for L, they might initially be at odds as they both are brilliant detectives, but they could end up working together to stop the misuse of the Death Note.