EFT transfer to an exchange, purchase crypto (1% fee), withdraw to a different exchange ($1 fee), sell crypto (1% fee), SEPA transfer to recipient.
Classic path:
TransferWise handles everything (0.85% or less). Or:
EFT transfer to Interactive Brokers, FOREX exchange ($20 per million), withdraw via SEPA to Croatian account. They allow you to link both AU and Croatian accounts. Or:
Open an HSBC account in both places and use the online instant account-to-account global transfer tool (rates vary, ~2%) and send a SEPA payment. Or:
Wire money (pricey). Or:
With a brokerage account and an established business you can instantly make your payment through margin (3.9% per annum). IB will allow you to borrow Hrvatska kruna and withdraw instantly via SEPA payment. Then you can transfer in Australian dollars over EFT at your leisure.
Seriously, this is a solved problem and the crypto path is not faster, it's not safer, it's not cheaper, it's not easier.