Obi - Wan Kenobi could be a great travel companion. Their relationship is so complex, and Obi - Wan could either be there to guide Anakin or to try and stop him from changing too much. Another possibility is Padmé. Since she was such an important part of Anakin's life, she could accompany him and influence his decisions during the time travel adventures.
Some fanfics might have Anakin time travel to a time when the Jedi Order was first founded. He could learn from the ancient Jedi teachings and bring that knowledge back to his own time to reform the Order. Or he could travel to a post - Galactic Empire era, seeing a galaxy that has either recovered or is still in chaos from his actions as Vader, which would be a huge motivation for him to go back and change things.
One great 'Anakin Skywalker Fanfic' is 'The Chosen One's Redemption'. It shows Anakin's journey towards redemption in a really interesting way. It delves deep into his inner turmoil and how he tries to make up for his past mistakes.
In a time - travel scenario, Anakin's relationship with his mother could be greatly altered. He could go back in time and save her from the Tusken Raiders. This would change his whole outlook on life and his path towards the dark side. Regarding his relationship with Palpatine, he would be aware of Palpatine's true nature from the start. So, he could either avoid Palpatine completely or try to expose him earlier. His relationship with other Jedi, like Ahsoka, could also be different. He could be a better teacher and mentor to her, as he has the experience of his future mistakes.
One idea could be Anakin traveling back in time to prevent his fall to the dark side. He could use his knowledge of the future to avoid the events that led him astray, like not trusting Palpatine. Another plot could involve him traveling to a time after his death and seeing the impact of his actions on the galaxy, which could be a moment of redemption for him. And perhaps he travels to a completely different era in the Star Wars universe and has to adapt to new cultures and powers while also dealing with his own inner turmoil.
One common theme is redemption. Since Anakin made so many mistakes in the original story, in time travel fics, he often tries to atone for his actions and make things right. For example, he might go back to save Padmé or prevent the rise of the Empire.
Yes, in some fanfics, Anakin Skywalker is made out to be a descendant of Revan. Writers like to create these connections to add more depth and mystery to the Star Wars universe they're crafting in their stories.
I really like the fanfic 'Anakin's Guidance for Rey'. In this story, Anakin, as a Force ghost, appears to Rey after she has started her Jedi training. He gives her advice on how to deal with the dark side of the Force, based on his own experiences. It has a lot of great dialogue and shows how Anakin has grown in his understanding of the Force even after his death.
His relationship with Obi - Wan would also change. If Anakin travels to a time when he was just a young Padawan again, Obi - Wan might see a different side of him. Anakin could use his future knowledge to become a better student, and Obi - Wan would be proud of him. Or, if Anakin travels to a time before he met Obi - Wan, he could approach their relationship from a new perspective when they do eventually meet.
One common theme is redemption. Since Anakin has made so many mistakes in the Star Wars saga, in fanfics where he's blind, it often becomes a starting point for him to re - evaluate his life and seek redemption. For example, he might rely more on his inner self and the Force to make amends.