The releases of both games on next-generation consoles were confirmed in a press release today, with an estimated release window for both games as Early 2021. Subnautica is already out on PS4 and its sequel will also launch on the console in Early 2021.
You can watch a trailer for Subnautica: Below Zero below:
Subnautica released back in 2018 on PS4 and its frozen sequel has been in development since then. The game is currently in early access and the developer Unknown Worlds commented back in 2019 that the release would be a way off. Its release was confirmed for Nintendo Switch earlier this year, but it is nice to have confirmation of a PS4 and PS5 release.