I am in the US and want to download an app, only in the US Store.
I tried changing the App Store Country, but seem to hit an impasse.
When entering my Credit Card details I cannot select Australia as the billing address.
I have 2 MasterCards, one Travel Money card with $US, and my Australian card.
I give up - this is apparently not possible!
I can't change App Store Country without changing Family Sharing.