You can transfer to any of those countries, but in most cases you can only receive in the relevant currency of that country. EG Switzerland can receive CHF, UK can receive EUR and GBP etc.
So to choose USD you have to choose 'United States' as the country - there's no option for Denmark where Revolut bank. Which means you need a US account number not IBAN, which fortunately Transferwise provide - here's a screenshot of the screen on stripe
You can transfer to any of those countries, but in most cases you can only receive in the relevant currency of that country. EG Switzerland can receive CHF, UK can receive EUR and GBP etc.
So to choose USD you have to choose 'United States' as the country - there's no option for Denmark where Revolut bank. Which means you need a US account number not IBAN, which fortunately Transferwise provide - here's a screenshot of the screen on stripe