The official Android 9.0 (Pie) beta ROM for the Galaxy Note 9 is now available. Not only does this software contain the latest OS update, it also replaces Experience with One UI, the revamped interface for Samsung mobile devices. So far, this beta is available in Germany, India and the US.
https://www.notebookcheck.net/One-UI-beta-for-the-Samsung-Galaxy-Note-9-now-available-in-some-countries.374206.0.html