I had 3 flex accounts plus a saving account with Nationwide when I came to Spain 25 years ago.
About 10 years ago I needed a credit card. I was told as I lived o/s UK, although I could keep my existing accounts, I could not open any new ones. A couple of emails to CEO and I got my credit card account
About two years ago NW withdrew one of my 3 debit cards and gave me a Cash card. Useless as I live in Spain. A couple of weeks ago they spontaneously cancelled the cash card and I now have a new Debit Card, so back to 3 debits and one Credit card.
All my accounts, except one, have my Spanish address. However, I had one card with an UK address, as it was convenient if I wanted something delivered in the UK (some suppliers will only do that if the account address is also in UK). I was told that was not possible, but after a chat on the phone, I now have one card with the UK address as the registered address.