from original post (can be found in the Mate 20 Pro forums)
Main changes from stock:
-iOS inspired dialer.
-Dark switches, system settings & quick settings icons.
-Changed brightness & volume sliders.
-Google sans font
-Darker text in some areas & and some system dialogue box backgrounds.
Download iOmix.hwt theme.
Move it to your Huawei P40/P40 Pro's storage (HUAWEI P40 Pro\ Internal shared storage\Huawei\Themes)
apply theme in "Themes" app.
Known issues, just in case.
Dark text on gmail "subject" notifications, dark controls on default music app notifications & dark status bar icons in the gallery app. These are caused by making the toggles, switches & quick settings black
DOWNLOAD LINK: http://bit.ly/2SLM3IA (orange)
For other accent colors, please go to the original thread HERE