The creativity. With oc x oc fanfiction in Descendants, authors can create entirely new characters with unique backstories, powers, and personalities. They can then build relationships that the original Descendants story might not have explored.
One great source for descendants oc x oc fanfiction is Archive of Our Own (AO3). There are many stories there that explore unique original characters in the Descendants universe. You can search by tags like 'descendants oc' and 'oc x oc' to find some really interesting reads.
Another theme is acceptance. The OC may be different from the descendants in many ways, but over time, they are accepted into the group. And in turn, the OC also has to accept the unique aspects of the descendants' world, like their different cultures and magic systems.
One common theme is the idea of forbidden love. Since Harry Hook is from the Isle of the Lost and often seen as a 'bad boy', the relationship with an OC (who might be from Auradon or a different place) goes against the norms of their world.
Another theme is friendship. The OCs usually form bonds with the characters from 'Descendants 2'. They might start as outsiders but gradually become an important part of the group. This is shown in many fanfictions where the OC helps the main characters solve problems through their unique perspectives.
A possible plot for a Descendants 2 Harry Hook OC fanfiction is that the OC is a healer on the Isle. Harry Hook gets seriously injured during one of his escapades, and the OC is the only one who can save him. This leads to a debt that Harry feels he owes the OC. As they interact more, the OC starts to influence Harry to think about a different life. Meanwhile, the OC has their own dreams of bringing some form of peace to the Isle, and Harry becomes an important part in making those dreams come true.
One great 'descendants Harry Hook x OC' fanfiction is 'Hooked on You'. It has an interesting plot where the OC character is a new student at Auradon Prep and catches Harry Hook's eye. Their interactions are full of tension and slowly developing romance.
To create a believable OC, start with a backstory. Maybe the OC grew up in a different part of the Isle than Harry Hook, which gives them a unique perspective. Give them flaws, like being too trusting or having a quick temper. Also, think about their appearance. Do they have a signature piece of clothing or a distinct hairstyle? For example, they could always wear a torn red scarf that was a memento from their parents. Their goals and motives should be clear too, whether it's survival, revenge, or something else.
One great 'descendants oc fanfiction' is 'The Lost Princess of Auradon'. It tells the story of an original character who discovers she has a hidden connection to the royal family of Auradon. The story is filled with adventure and self - discovery.
Wattpad is another option. There are quite a few 'descendants oc fanfiction' works on it. Some of the stories on Wattpad even have really cool illustrations or cover images that add to the overall appeal of the fanfiction.