Specialist international currency exchange companies including ASX-listed OFX, heavily backed TransferWise and Australia's newest "unicorn" start-up Airwallex are gearing up for a fight for survival, after Facebook's assault on the global financial services industry targeted free global transfers.

One of the clearest near-term aims of the mooted Libra blockchain and cryptocurrency ecosystem is to significantly reshape the way funds are transferred around the world, and ultimately give customers an option to send money for free via messaging services like WhatsApp.