A great plot could involve a Digimon evolving in a completely unexpected way during Summer Wars. This new form could have powers that are either a huge help or a big problem. For example, it might be able to manipulate the digital systems in the Summer Wars world, which could either fix glitches or create new ones. Or perhaps there's a love story between a Digimon and a human during Summer Wars. This would be a very different kind of relationship compared to the normal Digimon - human partnerships and could lead to all sorts of interesting situations.
One interesting plot idea could be the Digimon characters getting transported to a different digital world during the events of Summer Wars. They could encounter new types of Digimon and have to form alliances to survive. Another idea is that a human character from the Summer Wars universe somehow gains the ability to enter the Digimon world and has to learn how to control their newfound powers. Maybe a group of Digimon come to the human world during Summer Wars and cause chaos, and the main characters have to figure out how to send them back while also dealing with the normal chaos of the Summer Wars event.
Another plot could involve a journey across different planets in the Star Wars universe by Digimon. They could be on a quest to find a powerful artifact that can save both the Digimon world and the Star Wars galaxy from a great evil. Along the way, they meet various Star Wars species and have to overcome different challenges.
Maybe in this fanfiction, the Digimon are drawn to Naruto's world. The ninjas in Naruto's world are initially suspicious of these strange creatures. But as they learn more about the Digimon and their fight against the evil forces in the Xros Wars, they decide to help. And Naruto could teach the Digimon some of his ninja techniques, like how to use chakra.
Another plot idea is a crossover with a time - travel themed story. The characters from Summer Wars are sent to different time periods, like ancient Rome or the future. They have to adapt to the new cultures and technologies while also trying to find a way back home. Along the way, they might change historical events or gain knowledge that will help them save their own world from a potential threat.
One idea could be Davis getting involved in the Hunters' world by accident. Maybe he's exploring a new area and stumbles upon a digital gate that leads him there. Then he has to team up with the Hunters to face a new, powerful Digimon threat that is endangering both worlds.
Maybe the OC is a hacker who is on a mission in OZ and Kazuma gets caught in the middle of it. They end up having to work together to solve the mystery behind a new threat in OZ. As they spend more time together, they start to develop feelings for each other. For example, while they are decrypting codes and fighting off digital enemies, they share personal stories and find common ground.
A plot could involve a group of dark digimon forming an alliance to take over a particular area of the digital world. They start by targeting the weakest digimon settlements. The story could follow a young digimon trainer who tries to gather allies to fight back against this dark alliance. There could be many challenges along the way, like finding rare and powerful digimon to join the cause, and also dealing with the psychological warfare that the dark digimon use. For example, they might spread false rumors to cause distrust among the good digimon.
One idea could be an OC who has a unique bond with a Digimon that's not a typical partner. For example, an OC who can communicate with wild Digimon and uses this ability to stop an evil force from disrupting the Digimon world. Another plot could involve an OC Digimon Hunter who discovers a hidden power within themselves during a dangerous mission. Maybe they can temporarily fuse with their Digimon partner to gain super strength and defeat a powerful enemy.
A plot could revolve around a digimon human hybrid who discovers they have a unique digivolution ability. This ability might be a key to unlocking a hidden power within the digimon world that could either save or endanger both the human and digimon realms. Maybe this hybrid is initially ostracized by both humans and digimon for being different, but as they uncover the secrets of their power, they gain acceptance.
One idea could be that the Pokeballs and Digivices somehow get mixed up. So trainers start finding Digimon in Pokeballs and vice versa. It would lead to a lot of chaos as they try to figure out how to handle these new creatures. Another plot could involve a villain who wants to combine the power of Pokemon and Digimon for evil purposes, forcing the heroes from both worlds to team up.
Maybe there's a situation where the Digimon from both series start to lose their powers for some unknown reason. The characters from Digimon 02 and Tamers must journey together to find the source of this problem. They could encounter old enemies and new threats along the way. The Tamers' more technical knowledge and the Digimon 02 gang's experience in the digital world could be key to solving the mystery.