I am already working on a game and at the moment I can't work on 2 games at the same time so here is my idea: Pokémon Revolution.
A game in which at the beginning everything seems normal: you are a 10-year-old kid about to start a journey in the region, you choose a starter (you get to choose between every starter), you defeat gym leaders in order to earn badges and win the Pokémon league. But the more places you visit, the more you keep asking yourself questions like "Why am I living here?" or "Why does anyone ever move?". You talk about this to many people you encounter in your journey that, thanks to you, become conscious, this makes them get deleted and transformed into ghosts called glitches and their Pokémon into MissingNo (and its different forms) that is now a glitch type (super effective against dark, ghost, electric and steel, weak against fire, electric, ice and psychic, resists dark, ghost and steel, resisted by electric and psychic, immune to normal) Pokémon. Since you are the player, the game wouldn't exist without you and therefore you cannot get deleted.
Even though many people you become friends with end up being transformed into glitches, you keep going until eventually you arrive at the Pokémon champion that reveals to be a godlike entity that seems to have created everything: the game developer, who is trying to find a way to make you a glitch without destroying the game since the beginning as they want to play the game in first person. Unfortunately for you, in the exact moment when you arrive there, you get teleported in the glitch world but surprisingly are still alive. There, you come in contact with all the people you have lost and together manage to break through the computer and forbid the game developer to ever edit the game again. Though, this destroys the game and forces everyone to evacuate in the ultra-megalopolis in order to stay alive (imagine the ultra space as a parallel universe).
In the post game you travel through different dimensions using ultra wormholes in order to rebuild the world as you used to know it and becoming yourself a game developer who plays the game in first person.
In this game all Pokémon would be available and, depending on where you are, you can use mega evolution, z moves, dyna/gigantamax or terastalization.
Personally, I would 100% play this game and I hope that someone will actually make it.