There may not be mainstream, widely - publicized fanfictions with Obi - Wan gagged. But some independent writers might have created stories around this concept. It could be that in a story, Obi - Wan is gagged during a diplomatic mission turned hostile. His captors want to silence him to gain an advantage in negotiations. This could lead to a complex plot where his friends have to use their wits and skills to free him and resolve the diplomatic crisis.
Count Dooku could be a prominent character. Given his own fall to the dark side, he might be a mentor or a rival to Obi - Wan in the fanfiction. Mace Windu is another one. His strict view of the Jedi Code and his relationship with Obi - Wan could be explored in the context of Obi - Wan's turn. And of course, there are the various Sith Lords and dark side adepts that might surround Obi - Wan, either as allies or enemies in his new dark side life.
Often, Obi - Wan uses his mastery of the Force. He might use a Force - push to overpower his guards when they least expect it and then make a run for it. He could also use a mind trick on a high - ranking captor to order his release.
Jon Snow could be one. He has a sense of honor and leadership, much like Obi - Wan. They could bond over their shared values and Jon could learn from Obi - Wan's wisdom. Another could be Daenerys Targaryen. She is on a quest for power and Obi - Wan might see her as someone who needs guidance to use her power responsibly.
He might have adventures related to understanding the unique culture of the all - female planet. For example, he could learn about their social structure, which may be centered around female leadership and cooperation. Maybe he would encounter some challenges in communication as their values and ways of thinking could be different from what he's used to in the Jedi Order.
Ezra Bridger would be a great character to pair with Obi - Wan. Ezra is still learning about the Force, and Obi - Wan could be his wise mentor, teaching him more advanced techniques and the true nature of the Force.
In a time - travel story, Obi - Wan's character would grow in his understanding of destiny and the Force. He may see events that were meant to happen no matter what he does, like Anakin's fall, which could make him more accepting yet still determined to fight for the light side. He could also develop a stronger sense of leadership as he has to navigate through different time periods and deal with various threats. He might have to lead other Jedi in different eras, which would force him to adapt his leadership style and become more versatile.
If Obi - Wan travels back in time, his character would become more self - aware. He would have the knowledge of his past mistakes and would be more cautious. For example, in his relationship with Anakin, he might be more empathetic from the start, understanding Anakin's insecurities better. This would lead to a different dynamic between them, and perhaps Anakin would not be so easily swayed by the Dark Side. Also, Obi - Wan would be more confident in his Jedi abilities as he has already seen the heights and lows of the Jedi Order in his own time.