Gengar is a popular choice. Its already spooky appearance and ghost - type nature make it easy to incorporate into horror scenarios. It can lurk in the shadows, play tricks on trainers, or even possess other Pokemon to cause chaos.
Mewtwo is also often used. Given its powerful psychic abilities, in horror fanfiction it can use its powers to manipulate minds, create illusions that drive people mad, or even break the boundaries between dimensions to let in otherworldly horrors. Its origin as a genetically - engineered Pokemon also gives room for dark backstories and experiments - gone - wrong themes.
Pikachu is a very popular one. Since it's one of the most recognizable Pokemon, seeing it gender - swapped can lead to some really interesting scenarios. Charizard is also commonly used. Its large and powerful form can be re - imagined in a different light as a female or male - swapped.
Elizabeth Bennet is extremely popular. Her strong - willed and intelligent nature makes her a great character to put in new and different situations in fanfiction.
Pikachu is often a popular character. It's so well - known and loved in the Pokemon franchise, and in fanfiction, it can be the center of all kinds of adventures, like getting lost in a mysterious cave and having to find its way back to its trainer.
Pikachu is often a popular character in pokemon shipwreck fanfiction. Since it's one of the most well - known Pokemon, it can play a key role in helping the survivors. Ash Ketchum, as a trainer, is also commonly featured. His experience and bond with his Pokemon can be a central part of the story. Misty and Brock might also appear, with Misty's water - type Pokemon being useful in a shipwreck situation near water, and Brock's knowledge of Pokemon care being valuable for any injured Pokemon.
In Pokemon birth fanfiction, Misty can be a popular character. She has a strong connection with water - type Pokemon, and she could be involved in the birth of a water - type Pokemon, perhaps using her knowledge of water to create a suitable environment. Professor Oak is also a character that often shows up. His vast knowledge of Pokemon would make him a valuable asset during a Pokemon birth. And Pikachu, as Ash's most famous Pokemon, might also be part of the story, either as a helper or just being curious about the new - born Pokemon.
Charizard is quite popular in Pokemon muscle growth fanfiction. Its large size and natural strength make it a prime candidate for stories about muscle growth. Machamp is another one. With its already muscular physique, fanfiction often explores how it can further enhance its muscle power. And then there's Gyarados. The big, powerful water - type Pokemon can be depicted in fanfictions as growing even more massive muscles, perhaps due to some special underwater training.
Seto Kaiba is also often used. His ambition and his drive to be the best duelist could lead him to time - travel in search of more powerful cards or to prove his superiority in different eras. He might go back in time to challenge the greatest duelists of the past with his modern - day deck.
Eren Yeager is often used. His complex character arc in the original 'Attack on Titan' makes him a great candidate for crossovers. He can bring his determination and his unique Titan - shifting abilities to different fictional universes. Another popular character is Levi Ackerman. His combat skills and no - nonsense attitude are very appealing in crossover scenarios. He could hold his own against characters from other universes.
Mobius 1 is a very popular character often used. Given his status as a highly skilled pilot in the ace combat series, he makes for an interesting addition in crossovers. Another one is Pixy, his complex character and his relationship with Mobius 1 can bring a lot of drama to the crossover stories.
The colonists from Rimworld are often used as main characters. Their diverse skills and backstories make them interesting to pair with characters from other universes. For example, a skilled medic colonist could interact with a healer from a magical world.