who is he
In the past they would come out with a third "enhanced" title such as Emerald, Platinum and Crystal.
Now they released a pair of games after BW, which were BW2.
IMO it is entirely possible that the next games be single and not paired versions.
The third versions still went along with the first two. If you got any one version, you had to trade with another game to get all the Pokemon.
Of all the things we are uncertain about, whether the games will be paired or not is not one of them. Time and again Masuda has stated in interviews that having multiple versions--forcing players to interact with each other--is at the very core of Pokemon. So unless Game Freak wants to remove that, what makes Pokemon "Pokemon," we will see multiple versions continue into the future.
Removing multiple version removes trading. What is Pokemon without trading? So I have to agree with Pingouin7; just a remake of Emerald? Maybe if they had two all-new Hoenn games to go along with it with the same regional PokeDex, but that's just stretching it!