A really interesting plot twist might be if Etain was actually a double agent all along, but her feelings for Darman start to make her question her loyalties. This would not only change their relationship but also the overall story arc as Darman has to decide whether to trust her or not.
Darman might start as a more rigid soldier, but through his interactions with Etain, he could develop a softer side. For example, he could learn to understand the Force better and how it affects the people around him.
One interesting plot twist could be a hidden relationship between Solo and a character that was initially thought to be his enemy. For example, a smuggler who he meets during one of his heists turns out to be an old acquaintance from his childhood on Corellia, with a shared past that changes the course of their interactions.
Another plot twist might be that the heroes of Earth discover a long - lost connection between our planet and the Star Wars galaxy. For example, they find out that some of the advanced technology on Earth was actually given by an ancient Star Wars civilization long ago. This changes the whole dynamic of the invasion as they now have a different perspective on the invaders.
A really interesting plot twist is when a Jedi is able to turn Venom to the light side in some fanfictions. It goes against the usual dark nature of Venom and makes for a really unique story where the Jedi and Venom then fight together against the Sith.
One common plot twist is that Padme's captors turn out to be working for someone she least expects. It could be someone from within the Republic who has a hidden agenda.
One interesting plot twist could be that Ahsoka is forced to team up with a Sith to fight a greater evil. Maybe there's a new, powerful dark side force emerging that threatens both the Jedi and Sith ideals. This alliance would be full of tension as they constantly battle their own natures. Another twist could be that the Sith has a change of heart because of Ahsoka's influence. It's not a common occurrence for a Sith to turn towards the light, but her unwavering belief in the good could start to chip away at the Sith's dark facade.
One common plot twist could be that your self - insert character discovers they have a hidden connection to a major Star Wars character. For example, they might be related to a Jedi or a Sith. Another twist could be that the Mandalorian clan your character joins has a secret mission that goes against what they initially thought. Maybe they thought they were fighting for the good of the galaxy but end up realizing they were being used by a more sinister force.
One common plot twist could be Anakin having memories of his previous life right from the start. Instead of slowly realizing his destiny, he is immediately aware of the mistakes he made in his past life as Vader. This could lead to him making different choices much earlier, like not getting involved with Palpatine at all. He might also use his knowledge of the future to prevent certain tragedies, such as the death of his mother in a more direct way than in the original story.
In some fanfictions, Padme lives and is able to use her political influence to undermine the rise of the Empire. She forms a secret alliance with some Jedi who survived Order 66. This plot twist changes the entire political landscape of the Star Wars universe in the fanfiction. It shows how Padme's character, with her strong will and intelligence, could have been a major force in combating the Sith's plans.
A possible plot twist in the fanfiction could be that Kylo Ren has a secret plan all along that is not about power for himself but to actually save the galaxy in a very unorthodox way. He might be pretending to be on the dark side while secretly working against the real threat that the characters in the movie were not aware of. This would add a whole new layer of complexity to his character and the overall story.