The OnePlus Watch is official, and OnePlus will be launching it on March 23. The company has offered the briefest of teasers so far, but it has provided even more details about the OnePlus 9 series.
https://www.notebookcheck.net/OnePlus-confirms-that-the-OnePlus-Watch-will-launch-on-March-23-120-Hz-display-and-LPDDR5-RAM-for-the-OnePlus-9-series.527581.0.html