First come up with a shitty p2w mobile game to promote the forthcoming game, then abandon all buildup to the continuation of the main series and come up with a crappy "new" region that is shamelessly ripped off wholesale from a real-life region. Rip off yokai watch and force a pokemon-pokedex™ that you cannot get rid of and is always on the bottom screen. Heavily shill merchandise of this quirky new pal that you're just going to love.
Then come up with cringe super moves, and simultaneously, completely shamelessly, advertise a forthcoming plastic toy that connects with your game when you're doing those epic super-moves™. The following months will see heavy shilling of these moves, especially for those that are exclusive to kanto pokemon. Gotta have that prodigal son audience that lapped up the mobile game. Speaking of kanto, shill that to the extreme, including but not limited to "regional forms" that are just a shitstain slapped on an existing pokemon and then shill more, new merchandise featuring that.
The game's plot revolves around a creator's pet that is like Cynthia but about 1000 times more obnoxious. Approximately half of total game time is spent watching cutscenes featuring endless words from this bitch's mouth. Come up with a forced gimmick for this character that is brought up every second cutscene and then shill merchandise featuring said gimmick.
Remember to sweep under the rug all the removed content and mechanics. Now, when it's time for the rehash of this game next year, spend as much time lying and shilling about the nonexistant new features of this one, because if they bough last year's game they'll believe anything. Buy the press and shill notifications on everyone's 3DS that claim that everyone loves the "new" game and it is definitely not disliked by anyone. Force the games' shithole region and try to make people like it even though it and its games are nothing but full-frontal cringe overload. Double down on mobileshit afterwards.