The pokémon is Lucario and as the abilities to change typings willingly and is egg group is noted as universal.
In this world they are normal pokémon and they are corrupted pokémon, corrupted pokémon are pokémon who already have darkness in them or where corrupted by other character Pokemon it's a complicated thing to explain right now but I get to it.
For his haremwe have
Gengar
Another Lucario
scorbunny
lopunny
salazle/salandit
Gardevoir
meloetta
Garchomp
Flygon
etc. for now
Pokémon can also mega evolve without humans here (no humans in this world) and it's a permanent evolution no temporary transformation.
Most Pokemon will have to mega evolved and known as elders in this world and lead different Pokemon community throughout the world.
And there are multiple continents in the world. The main character goes around the world for exploration and goes around healing some of the corrupted corrupted pokémon and goes around freeing some of the villages. There are still gems here but they are known as battle arenas and are led by two arena guards/ combatans and after defeating them you earn and arena badge/emblem.