Huawei's P30 and P30 Pro were the only phones that were embedded with the latest EMUI software 9.1. The user interface built on the top of Android 9.0 offers a more optimized experience, a new file system, advanced gestures, and icon design. Mate 20, which includes Mate 20, Mate 20 Pro, Mate 20 X and Mate 20 RS, is launching beta testing of new software.
Beta is available for hands-free phones and requires 6GB of free space to test it. As is common with beta attempts, it's not a good idea to sign up with your driver's day phone.
Before upgrading to embedded beta software, you should note that this release does not support reboot capability, so you will need to wait for the upgrade to continue building beta to return to a stable version of EMUI.
For more details about the new features of EMUI 9.1, see the Huawei page.