Obviously, Cheryl is one of the main characters. She's the center of the fanfic's story. Depending on the plot, her Pokemon would also be important characters. For example, if she has a Pikachu, that Pikachu would play a role in her adventures.
Another theme is growth. Cheryl starts as a relatively inexperienced trainer and grows in skill and knowledge. In some fanfics, she learns about different Pokemon types and how to train them effectively. This growth can also be emotional, as she overcomes fears and insecurities.
There could be a story where Cheryl embarks on a journey to find a legendary Pokemon. Along the way, she meets different trainers and Pokemon, learns new things about the Pokemon world, and has to face her own fears and doubts. This type of story can be really exciting as it shows her growth as a character in the fan - created world of Pokemon.
One great Cheryl Pokemon fanfic is 'Cheryl's Pokemon Adventure'. It follows Cheryl as she embarks on a journey through the Pokemon world, facing various challenges and making new friends along the way. The story does a wonderful job of portraying Cheryl's character growth and her bond with her Pokemon.
Some Pokemon might grow thicker fur or develop ice - like coverings. For instance, Eevee could evolve into a new form with white fur and ice crystals on its tail. Fire - type Pokemon might have a frosty sheen on their bodies as a sign of the cold affecting them. Water - type Pokemon could have icicles forming on their fins.
One common theme is the exploration of different relationships. When ages are swapped, the way characters interact with each other changes. For example, an older - turned - younger character might have to re - establish their friendships. Another theme is the re - evaluation of goals. A trainer who is now younger might have different priorities in their pokemon journey.
There are fanfictions where a specific Pokemon species undergoes age regression. For example, a Charizard might be regressed to its Charmander state not just physically but also in terms of its behavior and understanding of the world. This can lead to interesting storylines about how it rediscovers things it already knew as a fully - evolved Pokemon.