If Luke never left, it would change a great deal. He was so important in uniting different groups within the Rebellion. His absence from the Jedi training might mean that the knowledge of the Force would be less widespread in the Rebellion. Also, his story of facing Vader was a turning point. Without that, Vader might not have had the change of heart that he did, and the fate of the galaxy could have been much darker.
If Luke never left, Obi - Wan's legacy might not have been carried out as he hoped. Luke was meant to be the new hope for the Jedi. Other Rebellion soldiers would miss out on the inspiration that Luke provided. Lando Calrissian might not have joined the fight in the same way without Luke's influence. And the Ewoks might not have had their moment of helping the Rebellion if Luke wasn't there to be part of that final battle on Endor.
Well, in such a fanfiction scenario where Luke is the emperor, he could have a very different approach to ruling than the previous emperors. Luke, being a former Jedi, would likely try to eliminate the corruption that was associated with the Sith - ruled empire. He might establish a more just galactic government, with an emphasis on peace and knowledge, using his unique understanding of both the Force's light and dark aspects.
If Luke becomes emperor in Star Wars fanfiction, the galaxy could see a new era of peace and justice. He might use his Jedi powers to root out the remaining Sith influence and bring about a more harmonious coexistence among different species. He would also likely reform the Imperial systems to be more fair and less tyrannical.
If Luke joined the Empire in a fanfic, it would be a complete deviation from his original path. He might use his Force abilities to rise quickly within the Empire's ranks. However, his friends like Han and Leia would likely become his enemies, leading to intense and tragic confrontations.
Well, Ezra and Luke are both strong in the Force. When they meet, they might exchange knowledge about the Force. Ezra could share his experiences with the Loth - Wolves and his time with the Rebellion. Luke, on the other hand, could talk about his training with Yoda. They might also team up to face a common enemy, perhaps an Imperial remnant or a new Sith threat.
In fanfiction, if Ahsoka meets Luke Skywalker, they could potentially train together. Luke, having been trained by Yoda and Obi - Wan, could share his knowledge of the Force with Ahsoka. Ahsoka, with her years of experience in combat and her own understanding of the Force, could offer Luke new perspectives. They might go on adventures together, facing new threats to the galaxy.
Well, it depends on how the fanfiction is written. He could meet his family in a completely different setting. Maybe they are all in a peaceful place that is far from the wars. His family might teach him new Jedi skills or knowledge that he didn't have before, which would make him even more powerful.
In the fanfiction, Ezra and Luke could form a strong friendship. Ezra could introduce Luke to some of the friends he made in the Rebels, like Sabine or Zeb. This could expand Luke's understanding of the different groups fighting against the Empire. They could also train together, with Ezra showing Luke some of the unique Force abilities he has discovered. And perhaps, they could even come up with a new strategy to take on the Empire's more powerful weapons or leaders.
In fanfiction, when Ahsoka meets Luke Skywalker, they might exchange stories about their battles against the Sith. Ahsoka could share her experiences with Anakin, which would give Luke a new perspective on his father.
Ahsoka and Luke meeting in Star Wars Rebels fanfiction could be really interesting. Ahsoka has a deep understanding of the Force and the Jedi ways, having lived through the Clone Wars. When she meets Luke, she may initially be cautious, given her past experiences. But as they talk, they could find common ground. Maybe they would embark on a journey to discover more about the Force and the ancient Jedi teachings. Luke's raw power and Ahsoka's refined skills could blend together to create a new kind of Jedi philosophy that would inspire others in the galaxy to rise up against the tyranny of the Empire.