If you change the time zone on your Huawei smartphone, a second clock is shown on the lock screen if the times differ. This function can be switched on / off and the time zone of the home city can be changed or selected.

Android 10 | EMUI 10.0
Dual clocks -  Open the  settings
Dual clocks -  Tap on  System & updates
Dual clocks -  Tap on  Date & time
Dual clocks -  Activate or deactivate  Dual clocks
  1. Open the settings
  2. Tap on System & updates
  3. Tap on Date & time
  4. Activate or deactivate Dual clocks

Huawei Instructions