In most cases, it is legal. Fanfiction is a form of creative expression by fans. As long as it doesn't violate any copyright laws in a major way, like using the exact same footage from the trailer without permission in a way that undermines the original work's marketability. But if it's on a legitimate platform that respects intellectual property, you should be okay.
The plot involves various characters boarding the Infinity Train. They have to face their inner demons, solve puzzles, and deal with the odd inhabitants of the train cars. The graphic novel explores themes like self - discovery and personal growth as the characters journey through the train's seemingly infinite expanse.
In fanfiction, some Avengers might be shocked. For example, Thor could be angry seeing Thanos' looming threat more clearly in the trailer. He might vow to stop him immediately.
Well, sometimes YouTube channels dedicated to fan content might feature or recommend Infinity War trailer fanfiction in video form. However, make sure it complies with YouTube's terms of use. Also, some specific fan communities on social media platforms like Reddit might share links or discuss where to find such fanfiction.
One interesting Infinity Train fanfiction could be about a character who discovers a hidden car on the train with a whole new set of rules. Another might be a story where two characters from different cars team up to overcome a common enemy on the train. There could also be a fanfiction that focuses on the backstory of one of the train's denizens and how they came to be there.
A fanfic could be centered around the younger Avengers like Peter Parker and Shuri. When they watch the Infinity War trailer with the rest of the team, Peter is in awe and can't stop talking about how cool it all looks. Shuri, on the other hand, is analyzing the technology shown in the trailer and starts giving ideas on how to improve their own gear. The older Avengers are both amused and impressed by their enthusiasm, and it brings a sense of hope and unity to the group as they face the impending threat shown in the trailer.
In some fanfictions, the Avengers might be shocked. They could see the looming threat in the trailer and start to strategize right away. For example, Tony Stark might start making sarcastic remarks while also thinking about how to upgrade his suit to face the new challenges.
One idea could be exploring the backstories of the characters in more depth before the events of the trailer. For example, you could write about Thor's journey after losing his eye and how it led him to where he is in the trailer. Another idea is to create a different perspective on the villain, Thanos. Maybe show his internal struggle or his reasons for wanting the Infinity Stones that are a bit more complex than just pure evil. You could also focus on the relationships between the Avengers, like how Iron Man and Captain America might have reconciled off - screen before coming together to face Thanos.
There could be a fanfiction where a group of friends, who are all huge Marvel fans, watch the Infinity War trailer together. They then start speculating about the possible plot twists and character developments. In the fanfiction, they might have a detailed discussion about how Thanos' character will be portrayed and what could be the fate of their favorite heroes like Iron Man or Captain America. It could also include their wild theories about new characters that might be introduced.