You can give them unusual magic powers. For example, the power to control shadows in a very distinct way, like creating living shadow creatures. Also, give them a unique backstory. Maybe they were raised by a group of magical beasts instead of humans. This would make their perspective and behavior different from the regular Fairy Tail characters.
To create unique characters, consider their appearance. They could have a very distinct hair color like a deep purple that glows in the moonlight, or eyes that change color depending on their mood. Their personality should also be a mix of different traits. For instance, being very shy in social situations but extremely bold when it comes to protecting their friends. And don't forget about their dreams and goals. If they have a goal to create a new type of magic guild that combines different magical disciplines, it would set them apart in the 'Fairy Tail OC Harem Fanfic' world.
To create a unique Fairy Tail Guardian OC, consider their personality traits. Instead of the typical brave and hot - headed like some of the Fairy Tail characters, your OC could be more calm and calculating. They analyze situations before acting. For their magic, it could be related to emotions. For instance, they can absorb the negative emotions of others and turn them into a powerful blast of energy. In terms of their look, they might have a tattoo on their face that glows when they use their magic, which is a sign of their guardian status.
You could give a character the power to manipulate the drinks in the bar. For instance, they can make a cocktail that gives temporary super strength or the ability to see through illusions. Just think of how that would interact with the other characters and the story.
You can combine the characteristics of robots and the magic from Fairy Tail. For example, a robot character could have a magic core that gives it special powers. It might be able to transform into different forms depending on the type of magic it absorbs. Another way is to give the robot a personality based on its function. If it was designed as a healer - type robot, it could be very gentle and nurturing.
You can give your Changeling character unique physical traits even when they change forms. For example, they might have a distinctive eye color that remains the same no matter what form they take.
You can start by changing their backstories. For example, if you want to make a unique Lucy, instead of being from a rich family, she could be an orphan raised by street mages. This would change her personality and how she approaches magic. She might be more street - smart and less naive.
For Earthland characters, you can draw inspiration from different cultures and mythologies on our own Earth. For example, if you want to create a mage with water - based magic, you could base their appearance and personality on the mermaids or water spirits from various folklore. In Edolas, since it has a different magic system, you could create characters whose powers are related to the technology - like magic there. Maybe a character who can manipulate the magical energy in machines.
Making the oc stand out in the Fairy Tail universe can be achieved in multiple ways. Firstly, their magical power source can be unique. For example, if most characters draw magic from within themselves or from natural elements, the oc could draw magic from dreams or emotions. Secondly, their role in the guild can be special. Instead of being a typical fighter or mage, they could be a healer with a combat - ready side. Thirdly, the oc's character development can be different. They could start as a very shy and reserved character and slowly transform into a confident and assertive leader within the Fairy Tail guild, which is a journey not often seen in the original characters.
First, consider different elemental backgrounds. For example, a Fire Nation girl who is an outcast because she doesn't believe in the aggressive ways of her nation. She could have a soft side and be interested in art or healing instead of fighting. Another way is to play with different personalities. A shy Earth Kingdom boy who is really strong in earthbending but lacks confidence in social situations. You can also mix in different species. Maybe a winged lemur - like humanoid who has a carefree and mischievous personality.
Create backstories that involve lemons. For instance, a character was born near a lemon tree that was blessed by a powerful fairy. This made her have special powers related to lemons. She could be a monster girl with fairy powers who uses lemons to make potions to help other monster girls. Her appearance could also be influenced by the lemon tree, like having lemon - colored hair or eyes.
Start with their name. A name can say a lot about a character. Then, develop their flaws. A perfect character is not believable. Maybe your OC is clumsy or has a quick temper. This can lead to interesting situations in the fanfiction. Their magic should have limitations. If they can fly, maybe they can only do it for a short time or it takes a lot of energy. And don't forget to show how they interact with the existing Fairy Tail characters. Do they admire Erza? Are they intimidated by Gildarts? These interactions can make the OC seem more real.