One possible plotline could be that Ed has been hiding her true gender to fit into a male - dominated society or group. Maybe she's afraid of being discriminated against. Another could be that she falls in love with someone who initially only sees her as a male friend, and then there's the big reveal.
In 'ed is secretly a girl fanfiction', a likely plotline is that Ed has a special talent or role that is typically associated with males in the story's setting. She keeps her gender a secret to hold on to this position. As the story progresses, her female identity might start to surface when she faces challenges that require her to be true to herself, like when she has to make a moral decision that goes against the male - only rules she's been abiding by.
Perhaps a plotline where Naruto, as a girl, has to face different challenges in the ninja world. Like, some male characters might treat her differently, either underestimating her or having romantic interests in her that she has to navigate while still trying to prove herself as a strong ninja. In this fanfiction, she could also form unique friendships with female characters that she didn't have as a boy.
One idea could be that Ed has to keep her true gender a secret while on her alchemic adventures to avoid discrimination in a male - dominated alchemic world. Another could be that she forms unique relationships with other characters who might suspect or eventually discover her secret.
One idea could be that as a girl secretly, Ed Elric might face different challenges in the male - dominated alchemist world. Maybe she has to hide her true identity while trying to achieve her alchemical goals.
One possible plotline could be Neville struggling to hide her true gender identity while dealing with the challenges at Hogwarts. Maybe she has to constantly come up with excuses for not participating in certain all - boy activities.
Perhaps a jealous rival. This person might be a male who is threatened by Ed's success or popularity. When they discover Ed is a girl, they could use this secret to try and drive her out of the group or community she's in. They might spread rumors or create problems for her.
A plotline could be that Keith is an undercover agent or spy, and being a girl would put her at risk in her mission. So she pretends to be a boy. As the fanfiction unfolds, she has to balance her real self and her false identity while also dealing with the challenges of her mission and the people she meets during it.
A possible plotline is that Hermione secretly marries a character who has a dark past. Maybe he was once involved with the Death Eaters but has reformed. They keep their marriage a secret because they know the wizarding community won't easily accept it. Hermione, being the strong - willed character she is, believes in his change and is willing to take the risk. In other fanfictions, Hermione might marry a character who is not from Hogwarts, like someone from Beauxbatons. They keep it a secret because of the potential rivalry between the two schools.
One plotline could be them trying to keep their relationship a secret from their friends and families at Hogwarts. They might have to be really careful during school events and Quidditch matches to avoid any suspicion.
One possible plotline could be the two of them trying to keep their relationship hidden from Ron, Ginny's brother. Since Ron is Harry's best friend, they might be worried about how he'd react. Another could be them sneaking around Hogwarts to have private moments together, like meeting in the Room of Requirement.
Maybe the story could focus on how Izuku, as a girl secretly, has different perspectives and experiences compared to her male counterparts. She might face unique challenges in a male - dominated hero society, like having to prove herself even more. And there could be a sub - plot about her developing a romantic interest in another character, but being hesitant because of her secret.