Recently, it has been seen that this update is rolling out in more countries out from China and which means it can be out there on your P30 phone anytime soon.
This Dual-View camera mode parts the screen into two views and uses the rear camera to work at the same time allowing you to watch the overall view of the game on the right side and a special zoomed view on the left side of the display.
If you want to check for the update manually you can do this to follow the instruction below:
Go to Settings > System > System update > Check for Updates. If an update is available, it’ll ask if you want to download it.
How to use Dual-View Video mode on Huawei P30 and P30 Pro