One possible plotline could be the protagonist, reborn as Ash, using their prior knowledge to quickly become a more skilled Pokémon trainer. For example, they might know which Pokémon are strong in certain situations and target those for capture first. Another plotline could involve the protagonist trying to change the fate of some of the Pokémon characters in the original story, like preventing certain Pokémon from getting injured in battles.
Well, sometimes in si reborn as ash fanfiction, the plotline focuses on the character's internal struggle. Since they are reborn as Ash, they have to deal with Ash's pre - existing relationships and reputation. They might feel pressured to live up to what everyone expects from Ash while also trying to inject their own personality. This can lead to some really interesting character development as they navigate between being true to themselves and fitting into the Pokémon world as Ash.
In some si reborn as ash fanfiction, a common plotline is the main character leveraging modern knowledge about Pokémon breeding and training techniques that Ash in the original series didn't have. This gives them an edge in competitions and battles. Also, there could be a plotline where the reborn Ash forms unexpected alliances with other trainers or Pokémon that were not part of the original story, which then leads to new adventures and challenges.
Obviously, Ash himself is a central and popular character. Since the whole premise is being reborn as him, his actions and growth are key. Pikachu is also extremely popular as it's Ash's constant companion. Another popular character could be Gary, as his rivalry with Ash is a significant part of the Pokémon story and can be explored in new ways in this type of fanfiction.
One interesting plotline could be the relationship between the oak and the ash characters. Maybe they start as rivals and gradually develop an understanding and friendship. For example, they might compete for resources in their magical forest setting at first, but then realize they can achieve more by working together.
One interesting plotline could be an Original Character (OC) who has a unique survival skill that helps the group in ways they hadn't expected. For example, an OC who is a master of herbal medicine and can use plants to heal the sick and injured in the post - apocalyptic world of 'The 100'.
One interesting plotline could be Ash encountering a rare and powerful Pokémon that isn't part of the original Kanto Pokédex. For example, a shiny Mewtwo that he has to befriend instead of battle. Another could be Ash getting lost in an uncharted part of Kanto and having to rely on his Pokémon's unique skills to find his way out, like Pikachu using its electricity to create a signal. Also, a plotline where Ash teams up with a group of Pokémon trainers who have different goals but they all learn from each other during their journey.
One possible plotline could be Ash gaining unique powers from Arceus. For example, he might be able to communicate with all Pokémon in a more profound way. Another could be that Ash has a special mission given by Arceus to save the Pokémon world from a great threat. And perhaps he has to face challenges that test his new - found relationship with Arceus and the powers it has bestowed upon him.
Another plotline could be Ash getting involved in some sort of virtual Pokemon world within the fanfiction that has unique rules and challenges. He could discover new Pokemon species that are exclusive to this gamer - themed world. This would add a whole new dimension to his adventures and his relationship with his existing Pokemon team as they all adapt to this new environment.
One possible plotline could be Ash and Dialga going on an adventure together through different time - periods, facing challenges unique to each era. Another could be Dialga using its time - related powers to help Ash in his Pokemon battles in unexpected ways.
One interesting plotline could be Ash and Alexa going on a special journey to discover a new type of Pokemon. They might face challenges like difficult terrains and other trainers trying to stop them.
Another plotline could be centered around a family secret that only they can uncover. This secret might be related to a special Pokémon or a hidden power. As they search for the truth, they also strengthen their brotherly relationship, facing various challenges along the way, like rival trainers who are also after the same secret.
In some fanfictions, there could be a plot where Ash has to protect Lillie from a group of evil Pokemon trainers. This would show his loyalty and courage, and also lead to some exciting battles and adventures. And their relationship could grow deeper through this process.