Depite carrying the Legends subtitle, it turns out that Pokemon Legends: Z-A is far more of a sequel to Pokemon X & Y than to its predecessor, Pokemon Legends: Arceus–and the clues have always been right there in the name.
As mentioned in GameSpot’s review of the latest Pokemon title, Legends: Z-A can easily be considered a sequel to generation 6 titles Pokemon X & Y–it’s set in Lumiose City just five years after the events of that game, and brings back many of that game’s characters, Pokemon, and even Mega Evolutions. Looking back, the game’s status as a sequel has always been right there in the name–following on from X and Y, the next letter of the alphabet is Z, then it would cycle all the way back around to A.
The name could also be a reference to Pokemon Z, a rumored Pokemon title that many expected would be released following X & Y. All the signs seemed to be there for a Zygarde-centered gen 6 sequel, following the long tradition of third Pokemon releases like Crystal or Emerald, but Pokemon Z never eventuated. Instead it took over a decade for X & Y to finally get its follow-up, even if the name also bears the Legends subtitle.