There’s a LOT that goes into global monetary policy. I know more than some, but it’s complicated in a way that’s not easy or quick to explain here.
So to try and keep it short, there’s at least a couple major trade-offs. First, it would be somewhat offset by Australian immigrants working in other foreign countries and sending money home to Australia. Second, Australia has global trade partners for a multitude of things and can offset imbalances through borrowing or lending through international trade if and when needed.
There’s really so much more that goes into it and it’s a bit different for every country, but that’s a broad idea of how it can balance out.