Well, one possibility could be that Anakin goes to Dathomir in search of some unique Force knowledge. Maybe he's heard rumors about ancient Sith secrets there.
Perhaps Anakin is on a mission to Dathomir. He could be seeking allies among the Nightsisters. They are powerful in the Force, and he might think they could help him in the Clone Wars.
In the fanfic, Anakin might go to Dathomir because he has a vision. This vision could lead him to believe that something on Dathomir is crucial for his path in the Force, or for the fate of the galaxy. So he embarks on this journey full of mystery and danger.
There could be a hermit or an outcast Jedi or Sith on Dathomir. Anakin meeting this character could lead to a great revelation. Maybe this character has been in hiding on Dathomir for years, observing the balance of the Force there, and Anakin's arrival disrupts that balance and forces an interaction that changes Anakin's perspective on many things.
One possible plot could be Anakin going back to a time before his fall to the dark side. He could use his knowledge of the future to prevent certain tragedies. For example, he might stop the Clone Wars from starting, thus saving countless lives. This would also give him a chance to redeem himself and perhaps even change the fate of the Jedi Order.
Well, in the fanfic, Anakin's skills would be a huge asset or a threat to the First Order. If he decides to join them, his combat abilities and knowledge of the Force could make the First Order even more powerful. However, if he realizes that they are on a wrong path, like the Sith - influenced path he once walked, he might use his skills to undermine the First Order from within. He could start by influencing the stormtroopers, showing them that there are other ways than blind obedience.
Well, he could either try to take over the First Order with his powerful Force abilities. Maybe he would see it as a new tool to gain more power and control in the galaxy.
The plot might center around Anakin's moral struggle. On one hand, he has the Jedi teachings, but on the other, his own past as a slave. This internal conflict could add depth to the story as he decides how far he's willing to go to free the slaves. He may also have to deal with the consequences of his actions in the eyes of the Jedi Council.
In this fanfic, Anakin could stay on Tatooine because he has a premonition of the dark side that awaits him if he leaves. So, he decides to stay and focus on bettering his home planet. He might use his natural piloting skills to start a small trading business, using his pod - racer as a start - up vehicle. This would keep him occupied and away from the events that lead him to the dark side in the original story.
One possible plot could be that Anakin discovers Palpatine's plan to destroy the remaining Jedi earlier than in the original story. This early discovery gives him the chance to turn against Palpatine and kill him to save the Jedi order. Maybe he finds some hidden evidence that convinces him once and for all of Palpatine's true intentions.
Perhaps Anakin tells the council about his doubts regarding the Jedi teachings. He might share his thoughts on how he feels the Jedi are too rigid in their ways and that it could be a weakness. For example, he could mention how their strict code might be pushing some Force - sensitive individuals away instead of guiding them. This could lead to a big discussion within the council about the future of the Jedi order and possible reforms.
Well, he might encounter the Nightsisters. Maybe he'll have to learn their unique magic or face their trials. He could also form an unlikely alliance with them against a common enemy.
Maybe Anakin would be shocked by the advanced technology in the future. He might see flying cars and towering skyscrapers everywhere.