One possible fanfiction could be about Ezra Bridger's struggle against the allure of the dark side. Maybe he has a vision of great power that could be his if he turns, but he remembers his friends and the teachings of the Jedi. He battles internally, with the dark side whispering temptations in his ear.
In a fanfiction, Ezra might be tricked into joining the dark side by a disguised dark side user. This person could pose as a friend in need, only to lead Ezra down a dark path. They could manipulate his insecurities and his desire to be a stronger Jedi.
In a fanfic, Ezra could be manipulated by an old acquaintance who has already fallen to the dark side. This person could convince Ezra that the dark side offers a quicker way to end the Empire's tyranny. Ezra, being young and somewhat impulsive, might be swayed by this false promise, gradually embracing the dark side's teachings and powers.
One possible scenario in a fanfiction could be that Ezra is lured to the Dark Side by the power it seems to offer. Maybe he gets frustrated with the slow progress of the Rebellion and the constant threat from the Empire. He might be tempted by a powerful Sith Lord who shows him visions of a galaxy where he has the strength to end all the chaos, but at a great moral cost.
In one idea for a fanfiction, the Empire creates a false prophecy that convinces Ezra that he is meant to rule the galaxy as a Dark Lord. They manipulate events and his emotions to make him believe that the Dark Side is his true path. He then starts to build his own army of Dark Side followers. But as he rises in power, he realizes that he has been deceived, yet by then it may be too late to easily return to the Light Side.
Ezra could resist the dark side by relying on his strong bonds with his friends. Their loyalty and friendship act as a shield against the temptations. For instance, when he has moments of weakness and hears the dark side's whispers, he thinks about how his friends would be disappointed, and that gives him the strength to fight it.
Ezra could be lured by a Sith artifact. It emits a strong dark side energy that begins to influence his thoughts. He starts to question the Jedi ways he has been learning, thinking that the quick power of the dark side might be better. But his loyalty to his friends in the Rebellion holds him back from fully embracing it at first.
There could be a fanfic where an ancient Dark Side artifact is discovered near the Ghost. The crew decides to study it, not realizing the danger. As they do, the Dark Side energy starts to affect the ship itself. Systems malfunction, and strange things start to happen. Kanan, with his Jedi knowledge, tries to figure out how to neutralize the artifact and save the Ghost from being consumed by the Dark Side.
Ezra could start to show signs of being drawn to the dark side through his growing anger. For example, if something bad happened to his friends and he couldn't save them, his anger could make him more susceptible to the dark side's influence.
One great Sabine and Ezra fanfic could be one where they go on a secret mission together. It might explore their growing bond as they face challenges. Maybe they have to infiltrate an Imperial base, and along the way, they learn more about each other's pasts. Their different skills, Sabine's artistry and combat skills and Ezra's connection to the Force, would make for an interesting dynamic during the mission.