Okay so, I have just finished a Unity 2D course and I have this idea for a game I wanted to make.

I want to make a Pokémon-like game that's called Pokémon Forest, it's called Pokémon Forest cause you will be able to play all the different Pokémon professors when they were young and trainers themselves. It's a huge open world game with every single region in it. Here are the main aspects of the game:

Playable characters:

Samuel Oak, who will be played in the Kanto region. His specialty will be the study of the relationships between people and Pokémon.

Jonas Elm, who will be played in the Johto region. His specialty will be the study of breeding patterns and interactions between Pokémon.

James Birch, will be played in the Hoenn region. His specialty will be the study of Pokémon habitats in correlation with human existences.

Oliver Rowan, who will be played in the Sinnoh region. His specialty will be the study of Pokémon evolutionary patterns.

Aurea Juniper, who will be played in the Unova region. Her specialty will be the study of Pokémon origins in relation to mythology.

Augustine Sycamore, who will be played in the Kalos region. His specialty will be the study of the new type of evolution: "Mega Evolution".

Noah Kukui, who will be played in the Alola region. His specialty will be the study of Pokémon moves and will sometimes get himself hit to study the moves.

Emily Magnolia, who will be played in the Galar region. Her specialty will be the study of the new type of Phenomenon: "Dynamax".

Base Story for every character:

The choice between three starter Pokémon that have Grass, Fire, and Water as their primary types (they will encounter them in some way)

A villainous team serving as the main antagonists of the game, so 8 different teams, 1 per character.

A rival who starts their journey at the same time as the player, and is found multiple times throughout the game, so 8 rivals, 1 per character.

The player challenges eight Gym Leaders, as well as the Elite Four and Pokémon Champion. Except for Noah Kukui, in Alola Gym Leaders are replaced by the island challenge.

Other aspects of the game:

It will be a 2D pixelated-like game.

GTA 5 style, you have 8 different playable characters which will all be playable and you will be able to switch between them whenever you want.

You play all the different pokemon professors when they were young.

The professors were 11/12 years old, so the game will take place around 50 years ago.

It's one big open world game where you can visit all the different regions: Kanto, Johto, Hoenn, Sinnoh, Unova, Kalos, Alola and Galar.

Every professor has to defeat its own evil team and later on they have to work together to beat one BIG team: Team Rocket.

The leader of team Rocket will be Giuseppe, Giovanni's father.

Team Rocket will be unlocked after every character has defeated the elite four (they can only defeat the elite four after they defeated their region's evil team).

You will be able to catch all 59 legendary Pokémon.

All the gym leaders will be different from the original games(except the ones who were pretty old in the original games)

The player is able to have six Pokémon with him at most, while additional Pokémon can be kept in the Pokémon Storage System, 8 different Storage Systems for 8 different players.

The playable characters will be able to trade Pokémon and items with each other.

Evolution via leveling up, trade, and evolutionary stones.

Every region will have its original Pokémon, so for example Kanto will have the original 151 Pokémon.

Every pokemon will have 1 or 2 types, there are 18 different types in total.

There will be 742 different moves, all from the original Pokémon games.

All moves will be TMs, except the Z-powered moves and moves who belong to that Pokémon (like Spirit Shackle for Decidueye).

The HMs will also be replaced by TMs, the Pokémon who were able to learn the HMs don't need the HMs to do the specific action. For example Diglett could learn Cut and Rock Smash,
so now it can Cut through trees and Smash Rocks without having to learn the move, you just need to have him in your party.

There will be a friendship system, however, there will be no Poké Pelago and Pokémon-Amie.

So this is it. I still need to make all the different storylines for the different characters. Does anyone have any tips on how to make the game not boring, cause it is a long ass game. I will give the different characters different specialties, so they will have different abilities or something. That will make it so that the player will want to play the different characters.

Thanks in advance!