One possible fanfiction could be that Ash gets injured during a Pokemon battle and is rushed to the hospital. Serena, being worried sick, stays by his side the whole time. She might bring him his favorite Pokemon treats to cheer him up while he recovers.
In the 'pokemon ash in the hospital fanfiction', it could be that Ash got poisoned during an encounter with a new and dangerous Pokémon. While in the hospital, he starts to have strange dreams about a powerful Pokémon he has never seen before. His friends come to visit him, like Misty and Brock. Misty might scold him a bit for being too reckless but also show her concern. Brock could be using his knowledge of herbs to see if there are any that can help Ash's recovery. And all the while, Ash is thinking about getting back on his journey as soon as possible.
In the hospital setting of a fanfiction, trainers would interact with their Pokemon in different ways. Some trainers could be using their Pokemon as emotional support for themselves while they visit sick friends or family. A trainer with a Snorlax might just sit beside it and feel comforted. Others would be guiding their Pokemon to do good deeds. For instance, a trainer with a Psyduck could be trying to get it to use its water - based attacks in a controlled way to help clean up small messes. Trainers would also be teaching their Pokemon proper hospital etiquette, like not running in the hallways.
In a hospital Pokemon trip fanfiction, Pokemon could engage in unique interactions. Some Pokemon with psychic abilities, like Alakazam, might be able to sense the distress of patients and communicate that to the medical team. Smaller Pokemon like Jigglypuff could sing lullabies to put patients to sleep. And Pokemon that can fly, like Pidgeot, could deliver messages between different wards quickly. Their presence would add an element of magic and comfort to the often sterile and intimidating hospital environment.
Pikachu is a very likely candidate. It's Ash's most iconic Pokemon and has a deep bond with him. Whenever Ash is in trouble, Pikachu often steps up to protect him.
Ash could be a Pokémon trainer with a different starting point in this fanfiction. Born in 1987, by 1997 he might have already made a name for himself in local Pokémon battles. He could have a team of Pokémon that he rescued from difficult situations, like a Charmander that was abandoned by its trainer. His story could revolve around giving these Pokémon a second chance and proving that Pokémon don't need to be 'perfect' to be strong.
The impact of Ash's loss in the fanfiction could extend beyond just himself. His Pokémon might also feel demoralized. However, this could also be an opportunity for them to grow stronger together. Ash could start training more intensively, seek new training methods, or even try to catch new Pokémon to strengthen his team.
One popular type of Pokemon Ash and Pikachu fanfiction might be adventure - based. For example, Ash and Pikachu could embark on a journey to a new and mysterious region filled with undiscovered Pokemon species. They might face challenges like difficult terrains and powerful, previously - unseen Pokemon. In this fanfiction, Pikachu's electric powers could be enhanced in some unique way, and Ash would have to strategize differently to overcome the obstacles.
Ash and Serena might meet some new and strange Pokemon in the hospital's garden. These Pokemon could have unique abilities that help in their recovery. For example, a small, furry Pokemon that can emit a soothing glow.