Darth Vader could be an unexpected ally in a time travel scenario. If Luke travels to a time when Vader was still Anakin Skywalker and on the verge of turning to the dark side, Luke could try to prevent his fall. In the process, Anakin might become an ally, using his skills as a powerful Jedi to help Luke in whatever mission he has in that time period.
A really interesting plot would be if Luke's time travel was accidental and he ended up in a parallel universe. In this universe, the roles of the Sith and the Jedi are reversed. He would have to figure out how to get back to his own universe while also dealing with the strange new world he's in. Here, he might learn things about the Force that he never knew before, like different ways to use it that are unique to this parallel universe.
One great Luke Skywalker fanfic to start with could be 'The Life and Times of Luke Skywalker' as it delves deep into his character, exploring his journey not just as a Jedi but also as a person. It gives a very in - depth look at his relationships, his growth, and his struggles, which is really engaging for any Star Wars fan.
If baby Luke time - travels to a post - apocalyptic future in the Star Wars universe, he could be the key to rebuilding the Jedi Order. His very existence could inspire the survivors to start anew. They might look at his pure connection to the Force as a sign that there is still hope for a better future, and they would protect and train him to become a great Jedi, changing the fate of the galaxy once again.
When traveling to the future, Luke could become more desperate. Facing a world in chaos or a new, powerful enemy, he'd have to quickly adapt and find solutions. This would make him more willing to take risks and use powers in ways he hadn't before. His view of the Force might also expand as he encounters new forms of it in the future.
One idea could be that baby Luke Skywalker time - travels to the era of the Old Republic. He could end up being found by a Jedi Master there and starts his training much earlier. This would completely change the course of the Star Wars timeline as he'd be much more powerful by the time the original trilogy events are supposed to occur.
It could be that Luke has a unique connection to the Force that gives him the power of time travel. He might have to enter a deep meditative state, and during this trance, he can project his consciousness through time. If he wants to physically travel, he has to use a great deal of his Force strength to fully materialize in another time.
Another interesting plot is Luke traveling to the future. He discovers a galaxy in chaos due to a new, powerful dark force. He has to adapt to new technologies and new forms of the Force while also finding a way to defeat this new threat. He might meet descendants of his friends and foes, which would add an interesting dynamic.
Well, one unique aspect is the different relationships. A female Luke might have different dynamics with Han Solo. Maybe there would be more of a romantic tension from the start. Also, with Leia, it could be a sister - like bond but with a different flavor, like they might support each other in different ways.
One popular theme is Luke's further training as a Jedi. Many fanfics explore what he could have learned beyond what was shown in the movies. Another theme is his relationships, like his friendship with Han Solo and Leia in more depth or potential romantic relationships. And there are also fanfics about Luke's role in rebuilding the Jedi Order, showing his leadership and the challenges he faces in that regard.