Can I use my Monzo card to be paid in another currency, for example, Australian Dollars (AUD $)?
Not really. There is a load of discussions here (click the title for context)
but the tl;dr is that Monzo will eventually introduce IBAN, but no fixed timeline, and no confirmation about non-SEPA international payments anyway.
If you need international payments consider Money, transferwise, revolut, or others.
Although we don’t yet support international payments, you could use a service like TransferWise to transfer a foreign currency amount into Monzo. However we only store currency in GBP so it would be converted into GBP at the Mastercard rate upon receipt.
Wouldn’t Transferwise convert the AUD to GBP?
Yeah, where the conversion happens would be dependent on the service used 