A great plot point could be Ash's attempts to participate in Pokémon battles. As a Pikachu, he would have to rely on his natural abilities and instincts. He might develop new battle strategies that combine his human knowledge with Pikachu's natural fighting style. Also, how he deals with the Pokémon League in this new form would be full of twists and turns.
The way Ash adapts to Pikachu's instincts could be really interesting. He might find himself being more drawn to shiny objects or having an urge to store food in a certain way. And his relationship with his own Pikachu (if it still exists in the story) would be very different. They could become like equal partners instead of trainer - Pokémon.
Well, he might start to see the world from a Pikachu's perspective. For example, he would experience the small size and how everything looks so huge. He could also find it difficult to communicate with his human friends in the normal way since he is now a Pikachu. Maybe he would have to rely on Pikachu's ways of expressing emotions like using electrical signals.
One possible plot could be that Ash is turned into a Pikachu by a strange spell cast by a mischievous Pokémon. As a Pikachu, he has to figure out how to communicate with his friends. His Pokémon pals at first don't recognize him, but Pikachu - Ash starts using his old battle strategies in a new way. For example, he tries to direct Pikachu's electric attacks in the same patterns he used to direct his other Pokémon's moves in battles. Eventually, his friends realize it's him and they set out to find a way to reverse the spell.
Well, in such a fanfic, a cool plot point might be that Ash, as a Pikachu, has to communicate differently. Since he can't talk like a human anymore, he has to find new ways to convey his thoughts and ideas to his friends. Also, there could be a plot where he discovers new powers that normal Pikachu don't have because he was once human. For example, he might be able to strategize better than a regular Pikachu in battles.
One idea could be that Pikachu suddenly loses its electric powers and Ash has to find a way to help it regain them. This could involve a journey to a mysterious place that is said to have the power to restore Pokemon abilities.
It could be Team Rocket as always. Since Ash is now a Pikachu, they might see it as an easy target to capture. They could have new gadgets specifically designed to catch Pikachu - Ash, and constantly try to get their hands on him throughout the fanfiction.
Well, one possible plot line could be Ash and Pikachu getting lost in a mysterious forest in the fanfiction. They might encounter rare and powerful Pokemon that they've never seen before. This could lead to Ash having to come up with new strategies to either befriend or battle these Pokemon, all while relying on Pikachu's unique abilities.
Well, perhaps Ash starts to idolize Pikachu after seeing its unique powers in a battle. He might try to imitate Pikachu's moves and even start collecting Pikachu - themed items.
Well, one interesting plot point could be how Harry adapts to his new snake form. Maybe he discovers new abilities like slithering really fast or having a heightened sense of smell. Another could be how his friends react. Do they recognize him right away or is it a struggle? And then there's the whole aspect of how he communicates in his snake form. Does he hiss in a way that can be understood by other magical creatures?
In this fanfiction, a plot point could be how Anakin's power manifests in his child form. Since he was already extremely powerful as an adult, as a child, it could be both a wonder and a danger. His raw power might be harder to control, and it could attract unwanted attention. Additionally, the story could focus on how Anakin's experiences as a child this time around impact his view of the Force. He might develop a new and unique understanding that could set him on a different path compared to his original one.
In this kind of fanfiction, Ash might find it really hard at first. He's used to being a human trainer, and suddenly becoming a Pikachu would be a shock. He'd have to learn how to control Pikachu's electric powers which he only used to command before.