Wow, I never knew you were such a good writer. Guess I should have paid more attention.

great story, I like the look into Ash's character. I think you really 'captured' him.

Don't listen to them, capitalizing the names of pokemon is a stylistic choice and nothing else. There is nothing grammatically wrong with making every pokemon species name a proper noun, or leaving them lowercase, either way is fine just as long as you remain consistent.

As for the story, it is a cute interpretation. It's funny to imagine porygon traumatizing Ash so badly. That episode didn't even technically exist around the world because of what happened. And it's funny to imagine Arceus visiting Ash.

For some reason, I was expecting a similar story where Ash would never own a raichu because he would never convince Pikachu to evolve.

...except for the part where Ash has met them in canon? Admittedly, you're horribly unclear about timeline here - nine years vs six months, so it's possible this happened after, but it kind of begs the question of why make it a porygon anyway. And why he doesn't just loan the pokedex to someone to get those last two. And how the pokedex even works in this case, since the anime one comes fully loaded and is just about helping trainers, while the game version requires you to actually catch them.

Anyway, words like porygon and magikarp shouldn't be capitalized, as they're not proper nouns. The only time you should capitalize a species is when it's being as the pokemon's name, as with Pikachu. (And the title should be capitalized properly too.)