Square Enix shared a special PV video on YouTube that ended with the phrase “NieR: Automata to be continued.” This suggests we could see a new NieR: Automata project, though the vagueness means it is uncertain if it could be related to the anime adaptation, a game, or book. Additional statements also confirmed current sales figures for that game and NieR Replicant.
First, here’s the “NieR: Automata to be continued” announcement video suggesting a new project like a game or other form of media is in the works. It’s specifically designed to honor the fact that this game passed 10 million units sold physically and digitally worldwide. That applies to the Switch, PS4, Xbox One, and PC versions of the game. At the 5:48 mark of the PV, the screen scrambles and the ominous text suggesting more is in development shows up.
Square Enix also shared new key art on social media honoring the sales milestone. That features 2B at the forefront, with 9S right behind her and A2 at the back.

As for the new sales figure update for NieR Replicant ver.1.22474487139, that wasn’t accompanied by a special video. Square Enix just took to social media to share the update. It’s now at two million copies sold worldwide digitally and physically. That takes into account the PS4, Xbox One, and PC copies.
There is a piece of art shared to commemorate that, however.

NieR: Automata is available on the Switch, PS4, Xbox One, and PC, the anime is on Crunchyroll, and Square Enix’s books division handled a number of spin-off books worldwide.