One idea could be that Phoenix Wright travels back in time to a case he previously lost. He then uses his future knowledge to find new evidence and win the case, completely changing the course of his career and the fates of the involved characters.
A plot twist could be that a villain from the Ace Attorney series uses time travel to frame Phoenix for a crime in the past. Phoenix then has to not only prove his innocence but also figure out how to stop the villain from changing the past in more harmful ways.
Maybe Mia Fey travels to the future and discovers that the legal system has changed drastically. She has to adapt quickly to this new system while also trying to figure out how to get back to her own time. This could involve her working with a future version of Phoenix or other characters.
One interesting plot twist could be when a character who was thought to be an ally is revealed to be part of the time - paradox conspiracy. This sudden change in their role can add a whole new layer of mystery and tension to the story.
One idea could be a Christmas party at the law office. Phoenix Wright could be trying to solve a small mystery during the party, like who stole the secret recipe for Maya's Christmas cookies. Another could be a case where the defendant is accused of ruining Christmas for someone and the ace attorney has to prove their innocence just in time for the holidays.
A great plot idea could be a female pirate character who is wrongly accused of piracy in the Ace Attorney court system. She claims she was only defending herself against a group of corrupt sailors who were attacking her. The Ace Attorney protagonist has to fight against the prejudice of the court towards pirates and prove her innocence. Another plot could be a situation where a pirate ship docks at a port in the Ace Attorney world, and a murder occurs on the ship. The local authorities try to pin the crime on the pirates, but the Ace Attorney character realizes that there are many other suspects on the dock who had motives to commit the murder.
One idea could be exploring the backstories of minor characters in the Ace Attorney series. For example, you could write about the life of a court clerk before they started working in the courthouse. Another idea is to create an alternate universe where the legal system has different rules. Maybe in this AU, evidence is presented in a completely different way.
A great plot could be that the ace in the fanfiction discovers a time-traveling device by accident. They then use it to travel to different historical events. They might end up changing something small in the past that has a huge impact on their present world. For instance, they could accidentally prevent an important scientific discovery from happening in the past. Now they have to travel through time again to fix what they've broken. This creates a lot of suspense and adventure.
One idea could be to explore a case where the main character has to defend a supernatural being. It would add an element of mystery and the need to adapt legal strategies to non - human circumstances.
One idea could be a high - school - aged Phoenix Wright taking on his first case in the school's mock trial club. He has to prove his classmate innocent of stealing a valuable school trophy. Another could be a love triangle between Miles Edgeworth, Phoenix, and a new character in the high - school setting, which adds drama to their already competitive relationship. And a third idea might be a group of students including the main Ace Attorney characters starting a detective club in high school and solving mysteries around the campus.
Another plot idea is that there's a new disease outbreak in the hospital, and there are suspicions of foul play. Ema, with her scientific knowledge, starts to investigate. She could find evidence that points to a pharmaceutical company trying to cover up their faulty product. The Ace Attorney characters then come in to fight for justice in the courtroom based on the evidence Ema provides.
Research the time periods they'll be traveling to. If a character is going back to a certain era in the Ace Attorney universe, understand the social norms, legal systems, and technology of that time. This will help the character's actions and reactions seem more believable. For instance, if they're in a time with less advanced forensic technology, they'll have to rely more on traditional detective work.
One idea could be a story where Klavier and Athena work together on a complex case. They start off with different perspectives but gradually learn from each other and form a strong bond. Klavier's cool and collected nature contrasts with Athena's more emotional and empathetic approach, which makes for an interesting dynamic.