One idea could be to have Ash start with a different type of Pokémon that is not commonly chosen in the main series, like a Skorupi. The story could revolve around the challenges he faces in training it as it has a somewhat menacing appearance and is a Poison - type, which might make some people in the Pokémon world a bit wary. This would lead to interesting interactions with other trainers and gym leaders.
Perhaps Ash could start with a Togepi, but instead of it being a cute and innocent journey like in the anime, the Togepi has some sort of special power that attracts the wrong kind of attention. Ash has to protect it while also trying to figure out how to train it and help it control its power. He might have to seek out rare Pokémon or trainers who know about Togepi's kind to get advice.
In this fanfiction, perhaps Ash starts with a Eevee. Since Eevee can evolve into multiple forms, it would add a whole new dimension to his journey. He could face different challenges as he tries to decide which evolution path to take for Eevee, and it would also attract different kinds of Pokémon opponents.
Well, if it's 'Ash gets a different starter fanfiction', perhaps he gets a Bulbasaur as his starter. This would lead to him being more involved in grass - type Pokémon battles and strategies. He could end up exploring different regions in search of rare grass - type Pokémon to strengthen his team. Also, his personality might develop in a different way, as Bulbasaur has a calmer and more patient nature compared to some other starters, which could influence Ash's own temperament over time.
Well, 'different starter ash fanfiction' could refer to fan - made stories that start in an unusual way with the character Ash. It might be stories where Ash begins his journey in a completely new setting, like in a parallel Pokemon world where the rules are different.
Another possibility is that an old rival of Ash's, who has always been jealous of his success, becomes the main antagonist in this fanfiction. When Ash chooses a different starter, this rival sees it as an opportunity to finally defeat him, thinking that Ash's new and untested starter will be his downfall.
It could be a trainer who has a starter that has a type advantage over Ash's new starter. For example, if Ash has a Squirtle and the antagonist has an electric - type starter like Pikachu, they would constantly be in conflict. The antagonist might be jealous of Ash's skills or the potential of his Squirtle and try to undermine him at every turn.
If Ash had a different starter like Bulbasaur in fanfiction, his team composition would change significantly. He might focus more on grass - type Pokemon to complement Bulbasaur's abilities. His travels through different regions could be affected as well. Maybe he would be more drawn to areas with more plant - life where Bulbasaur could thrive. Also, his interactions with other trainers having fire - type starters would be more interesting due to type advantages and disadvantages.
Well, it could start with Ash being in a new region where Treecko are very rare. He stumbles upon a young Treecko that is being bullied by other Pokémon. Ash steps in to protect it, and Treecko, seeing Ash's kindness, decides to join him. Their journey together focuses on exploring the unique ecosystems of this new region. Treecko has to adapt to new battle styles and opponents. Ash and Treecko also befriend a group of local Pokémon trainers who help them understand the secrets of the region. In the end, they face a powerful trainer who has a team full of strong Pokémon, and they have to use their combined skills and the knowledge they've gained to win the battle.
Another idea is Ash starting with a Bulbasaur. His journey could focus more on nature and plant - type Pokemon evolution. He might get involved in more environmental - related plots, like helping sick plants in the forest with Bulbasaur's powers.
The plot could involve Ash and Chimchar facing a series of challenges in a new Pokémon league. They might encounter a powerful villain who has a special device that can nullify Chimchar's fire attacks. Ash then has to find a way to train Chimchar to use its other skills, like its speed and agility, to defeat the villain's Pokémon.
One possibility is that Ash discovers a young Rayquaza at the start of his journey. Maybe it's injured and Ash nurses it back to health. This could lead to a strong bond between them, and Rayquaza could become his most powerful Pokémon, helping him in battles against tough opponents like Team Rocket or other powerful trainers.