"I need Emulator support of Windows 10 Continuum for Phones"
You don't really need an emulator. Instead of thinking of screen size, think window size. As you reduce the size of the app you re-organize the placement and the layout of your app. You can see this if you resize Groove or the map app (on Windows 10).
@MaulRiEEZZZ just position and resize the advertisement based on the screen/window size that is available.
Adapting the UI of an app to a small size is also very useful on a desktop where I may not want the app to take my entire screen, makes room for other apps.