In the specific sense in which they were presented, as a result of possession of a Pokémon which was then 'imbued' with darkness (which portrays the original Pokémon as kinda lame, but anyway), it's unlikely because that's too tied to the plot of the games it was present in, and they're unlikely to want to use the same teams, same plot points, etc. In the generic sense in which dark versions of Pokémon might be interesting, they could try it although recent games haven't really had an aesthetic which would complement that, but whether they'd want to use the same name is ambiguous. Including them in the games, without centering these around them, would be an incitation to use them rather than, as in their earlier appearances, to effectively get rid of them, and as such it might not be likely to see much along those lines until they can go somewhere with it.