A cool plot could be about a group of Pokemon in the Reborn area that are affected by a mysterious energy source. This energy causes them to start transforming into different Pokemon species. A young trainer decides to study this phenomenon and in the process, uncovers a dark secret about a powerful organization that was responsible for releasing this energy. They then have to stop the organization from causing more chaos with the Pokemon transformations.
Well, a plot could involve May finding a magical artifact that accidentally causes TF (transformation) in all the Pokemon in a certain area. As she tries to fix it, she teams up with some of the transformed Pokemon who still retain their intelligence. They go on an adventure to find the source of the magic to reverse the changes. Maybe there's also a sub - plot where May has to prove to some skeptical trainers that these transformed Pokemon are still worthy of care and training.
Well, consider a plot where the trainer catches a Pokemon that has the ability to TF into objects or even other trainers. This could lead to some really comical and confusing situations. For example, it could transform into a Pokeball to avoid being caught by another trainer. It could also transform into a key item in the Pokemon world, like a Master Ball, and the trainer has to figure out how to get it back to its normal form without losing it forever.
One idea could be the main character being reborn as a Pikachu and having to navigate the world with its electric powers while making friends with other pokemon. Another could be being reborn as a Eevee and having the unique ability to evolve into any form at will, which causes both envy and admiration among other pokemon. Maybe the reborn pokemon has memories of being a human and uses that knowledge to outwit trainers and other threats.
One idea could be a story where the protagonist discovers a hidden power within a seemingly weak Pokemon in the Reborn region. This power could be the key to saving the region from a new, mysterious threat.
One idea could be that Ash gets transformed into a Pokémon and has to figure out how to communicate with his friends. Another could be that Team Rocket manages to use a new device to transform Pikachu into a different type of Pokémon. Maybe Ash and Team Rocket end up having to team up when a new, more powerful villain emerges who wants to transform all Pokémon into mindless servants.
Another idea is that the Pokemon have some of the abilities of the TF2 characters. So, there could be a Pikachu with the Scout's double - jump ability. Or a Snorlax that has the Heavy's strength and can use a 'Mini - Gun' - like attack which is actually just a powerful Tackle. This would create really unique and interesting battles.
One idea could be being reborn as a Pikachu and having to use your cuteness and electric powers to befriend other Pokemon and outwit Team Rocket. Another could be reborn as a Eevee and the journey to decide which evolution path to take while facing different challenges in the Pokemon world. Maybe being reborn as a Magikarp and trying to prove that you're not just a weak Pokemon but can become a powerful Gyarados through hard work and determination.
Another plot idea is that the reborn infant Pokémon discovers a hidden power within itself that was not known in the Pokémon world before. This power could be related to the fact that it has a human soul or consciousness. As it grows, it has to learn how to control this power while also dealing with the normal challenges of a Pokémon's life, like finding food and avoiding predators.
A possible plot could be that Mewtwo, in an attempt to protect Ash from a powerful and mysterious enemy, undergoes a self - imposed TF. This transformation gives Mewtwo the ability to access a hidden power within itself. Ash, on the other hand, has to figure out how to communicate with this new - formed Mewtwo and together they face the common foe. Throughout the story, their relationship evolves as they learn more about each other's capabilities.
A more complex plot could involve a mysterious force that is causing glitches in both worlds. Some characters from Overwatch and TF2 have to work together to figure out the source of this force. For example, Tracer from Overwatch and Scout from TF2 could use their speed to scout out the affected areas while their respective teams of engineers, like Torbjörn and Engineer from TF2, try to fix the glitches in the technology.