One way is by focusing on the character development. Since it's an oc in Anakin's shoes, really exploring how they grow and change in the Star Wars universe. Show how they struggle with Anakin's pre - existing relationships and how they make them their own.
Well, in such a fanfiction, the oc reborn as Anakin could have different relationships. They might not be as easily influenced by Palpatine as the original Anakin was. Since they are a different person inside Anakin's body, they could form new alliances and rivalries. They could also have a different approach to their relationship with Padmé, perhaps being more cautious or open, depending on the nature of the oc.
One great Anakin Skywalker fanfiction is 'The Chosen One's Redemption'. It delves into Anakin's journey towards redemption after his fall to the dark side. It shows his internal struggles and how he tries to make amends for his past actions. Another is 'Anakin in Exile' which imagines Anakin living in seclusion and reflecting on his life. It gives a deeper look into his character outside of the main Star Wars narrative.
In fanfiction, Anakin's character can be expanded through alternate timelines. Let's say a fanfic has him not turning to the dark side. We can then see how his character would have developed as a powerful Jedi without the influence of the Sith. It also allows for exploring his relationships with other characters like the clones in ways that the movies didn't fully cover. Writers can create scenarios where Anakin has to lead the clones in different battles and how that shapes his leadership skills and his view of the war.
An OC can stand out by having a unique power. For example, a power that is not based on ki but on something else like the power of sound. They could use sonic blasts or create illusions with sound waves. This would be different from the typical ki - based attacks in Dragon Ball.
To make it stand out, give the OC a really unique backstory. Maybe they were a scientist in their past life and now they're trying to use scientific principles in the world of chakra. Also, create new and unexpected relationships. Instead of just befriending the main characters, have the OC form bonds with minor characters and change their fates.
The Rinnegan OC can stand out by having a moral code that is different from the typical characters in the gamer fanfiction. For instance, they might use their powers not just for victory but also to protect the virtual world's inhabitants in a more selfless way, which would make them a more complex and interesting character.
An OC could stand out by having a special skill or talent. Maybe the OC is an amazing cook and can make the most delicious food. In a world where battles and magic are common, this simple yet appealing talent could draw in characters from the series. They would be intrigued by this different side of the OC and gradually form a harem around them. It also gives a chance for some cute and comical interactions, like when the characters are all eagerly waiting for the OC's next meal.
There are many good ones. Fanfiction gives a chance to expand on their relationship in ways that the official canon might not have fully explored. For example, some stories might explore what could have happened if certain events in the Clone Wars had turned out differently regarding their relationship, or they might focus on their unspoken emotions and how they could have developed further.
You can start by searching on popular fanfiction websites like FanFiction.net or Archive of Our Own. Use specific keywords such as 'Anakin Skywalker' along with other relevant terms like 'Jedi', 'Padmé', or 'Darth Vader'. Check the ratings and reviews of the fanfictions to see which ones are highly regarded by other readers.
Often, it would be depicted as a very emotional moment. Luke might be filled with a mix of awe, anger (for Anakin's past as Vader), and longing for a true father - son bond. Anakin could be shown as a figure full of remorse, reaching out to Luke in a desperate attempt to make amends.