Hehe, let me recommend Pokémon: Unlimited Coins to you! The male protagonist had unlimited gold coins at the beginning of the game. He could buy any Pokémon he wanted. Moreover, the system could also buy Pokémon of different levels! There was also a Super Divine Beast that was exactly the same as the one the members of the Flame Team had created. The male lead was so powerful that even the non-champion powerhouses could not defeat him. This novel is similar to the Pokémon Trainer named Aaron that you provided. It should suit your taste. I hope you like this fairy's recommendation. Muah ~😗