According to RPRNA, the Galaxy Note 9 (Model Number: N960N) One UI 2.0 beta (Android 10) testing has started and the software version of this update is N960NKSU3ZSK2. The software version may vary after final testing.
The publication also said that the Galaxy Note 9 One UI 2.0 beta program will start soon in South Korea, which should be available to more supported regions (like the Galaxy S10 and Note 10 series).
Check the screenshot below: You can see the Model number, country code, latest OS, and the build version, ZSK2)
Additionally, Samsung may soon start the One UI 2.0 beta testing for the Galaxy S9 series.
Note: Samsung didn’t officially confirm the One UI 2.0 beta program for the Galaxy Note 9, but it is confirmed that the Note 9 and S9 series will receive the One UI 2.0 update.