Well, one interesting plot point could be Ash encountering new and rare Pokémon in Sinnoh that he's never seen before. Maybe he discovers a unique form of a Pokémon that's native to Sinnoh. Another could be his interactions with the Sinnoh gym leaders, like having intense battles or forming unexpected friendships with them.
In some 'Ash goes to Sinnoh fanfiction', a cool plot point might be Ash getting involved in Sinnoh's local Pokémon contests. Since he's mainly focused on gym battles, this could be a new and exciting challenge for him. He could learn different strategies and techniques from the contest participants. Also, his Pikachu might have some interesting interactions with Sinnoh - specific electric - type Pokémon.
Well, in many fanfictions about Ash working in Sinnoh with his skills, one key plot point could be his unique Pokemon training methods. For example, he might use his battle experience from previous regions to train his Sinnoh Pokemon in new and unexpected ways. Another plot point could be his interactions with the local trainers. He could learn from them and they from him, leading to some interesting battles and exchanges of strategies.
He could make friends with Dawn. She's a well - known character in Sinnoh and her knowledge of Pokémon contests could be really helpful to Ash. Another potential friend could be Barry. His energetic and competitive nature would make for some interesting interactions with Ash.
One plot idea could be Ash and Misty getting separated from their group in Sinnoh and having to rely on each other to survive in a strange, new area. They could encounter a rare and powerful Pokemon that neither of them has seen before. Another idea is that they discover an ancient mystery in Sinnoh related to a type of Pokemon evolution that was thought to be lost. This could lead them on a journey to uncover the truth and help a particular Pokemon evolve in a new way.
One interesting aspect could be the character development of Ash in the Sinnoh League within fanfiction. Writers might explore his relationships with his Pokémon in greater depth, like how his Pikachu might face unique challenges. Another could be the battles. Fanfictions might create new and exciting battle scenarios that we didn't see in the original Sinnoh League arc. Also, they could introduce new characters or give more backstory to the existing ones in the Sinnoh League setting.
Well, perhaps in this fanfiction, Ash is on a solo quest in Sinnoh to find a way to improve his Pokémon training skills even further. He could be traveling from one town to another, meeting new trainers who give him unique tips. Along the way, he might encounter some legendary Pokémon that test his abilities in unexpected ways. This would not only be a great adventure for Ash but also a chance for him to grow as a trainer without the help of his friends.
Perhaps in this fanfiction, Ash has formed stronger bonds with his Pokémon. These bonds allow them to perform at their best in battles. His Pikachu might have learned a new and super - effective move. Also, Ash could have received some secret training from a Sinnoh Pokémon master who taught him unique battle techniques. This would all contribute to his victory in the Sinnoh League.
One possible plotline could be Ash starting his journey in Sinnoh and quickly befriending a rare Pokémon that is shunned by the local trainers. He then has to prove the Pokémon's worth. For example, it could be a shiny Zubat that is thought to bring bad luck. Ash, with his determination, shows everyone that it can be a powerful and loyal partner.
In some fanfictions, Ash and May might get involved in a mystery in Sinnoh. For example, strange events are occurring that are affecting Pokémon behavior. They work together to solve the mystery, with Ash using his battle skills and May her knowledge of Pokémon contests. As they dig deeper, they find that an ancient power from Sinnoh's past is being misused.
His first Sinnoh Pokémon could be a Chimchar. Imagine Ash finding Chimchar being bullied by some other Pokémon. Ash steps in and Chimchar decides to join him. Chimchar's energetic and mischievous nature would add a lot of fun to Ash's Sinnoh adventures as it grows and evolves into an Infernape.
Ash could develop his character in Sinnoh by becoming more strategic in his battles. Since Sinnoh has a variety of strong and unique Pokemon, he'd need to think more carefully. Misty could develop by becoming more independent. Maybe she takes on some solo adventures in Sinnoh, away from Ash for a bit, and this helps her grow as a trainer.