As i understand it, the trope is simply two versions of one game. In that sense The Oracle games count because even though the maps and levels are different, the plot is one half of the full plot of both games together and they share characters and other elements. and were developed and released as two versions of one game, not two games built from the same engine.
Not to mention they were also released at the height of Pokemon's mainstream popularity, like the Bomberman Max
series and other examples.
don't count because each episode is typically not the price of a full game, but when you add up all the chapters it is.
why not just change the trope picture to a Pokemon Pair, they're the Trope Codifier