A cool concept could be that the flux capacitor in the DeLorean gets a power boost from the Force. This allows Marty to travel not just through time, but also between different planets in the Star Wars universe. He could end up on Endor and help the Ewoks in a new way, using his knowledge from the future. Another concept is that Darth Vader discovers the DeLorean and tries to use it for his own evil purposes, like traveling back in time to stop Luke Skywalker from being born.
One way to write this fanfic is to think about the themes. Both Back to the Future and Star Wars deal with the idea of destiny. So, your story could revolve around how Marty's destiny in his own universe is somehow linked to the fate of the Star Wars galaxy. You could also play with the concept of time differently in the two universes. In Star Wars, there's a more linear view of time in a sense, while in Back to the Future, time - travel is a central mechanic. Combine these ideas to create an interesting narrative. For instance, what if Marty's actions in the Star Wars universe change the future of his own world in unexpected ways?
Another popular trope is the 'power transfer'. In some fanfictions, the idea is that the time - traveling capabilities from Back to the Future could somehow interact with the Force in Star Wars. Maybe a character from Back to the Future gains the ability to use the Force because of a time - space anomaly, or a Star Wars character gets access to time - travel technology and uses it in unexpected ways to change the course of the galaxy's history.
One common crossover is the idea of time - traveling in the Star Wars universe like in Back to the Future. For example, a character from Star Wars might use a device similar to the DeLorean to go back in time and change key events in the Galactic Civil War. Another crossover could involve the character personalities. Maybe Luke Skywalker and Marty McFly team up. Marty's street - smart attitude could complement Luke's Jedi - trained discipline.
One way to blend the two universes could be through time travel. In a fanfiction, perhaps a character from Back to the Future accidentally travels to the Star Wars galaxy. They could introduce advanced Earth technology to the Star Wars characters, like the hoverboard, which might be used in lightsaber battles for added mobility. This would create a whole new dynamic in the Star Wars universe.
He could be involved in diplomatic efforts that prevent a large - scale war. Given his knowledge of different cultures and his own experiences, he would be well - equipped to negotiate treaties and resolve conflicts. This would have a significant impact on the future stability of the galaxy.
I'm not sure specifically as it depends on the fanfic. It could be new characters created by the fanfic author who are descendants of the well - known Star Wars characters. For example, a grandchild of Luke Skywalker might be a main character, carrying on the Skywalker legacy in new ways.
Luke Skywalker and Marty McFly are often popular choices. Luke's heroism and Jedi powers combined with Marty's relatable and adventurous nature can make for great stories. Another popular combo is Darth Vader and Doc Brown. The contrast between the dark, powerful Sith Lord and the eccentric inventor can create a lot of drama and humor in a fanfiction.
Galen could find himself in a future where the remnants of the Empire are making a comeback. He would then have to decide whether to side with the New Republic or try to reform the Empire from within. In a fanfic, this moral dilemma could be explored in great detail, showing his internal struggle as he weighs the pros and cons of each option.
In a fanfic where Revan teleports to the future, he might be shocked by the advanced technology. He could find himself in a world full of strange new ships and weapons that are far beyond what he knew in his own time. Maybe he'd try to adapt and use his old skills and knowledge to navigate this new era.