What about adding funds using your region and your credit card/PP and then using VPN to purchase a game. Would that work or it will ask for billing info from the new region before even letting you use your wallet balance?
You should use PayPal, not a CC or DC. Of course, a Gift Card is highly recommended.
If you don't intend to sell the accounts, you can use the same credentials (e.g. phone number) and it wouldn't be a problem. (at least in my case)