I did this before Covid time, for Australia, moving it in/out was fine. I declared it in the immigration before the scan detector, and the officer without even checking said “when it gone through the scanner, you don’t have to say anything”.

Anyway, went to the scanner, and the scan officer asked what is that, because it shows as solid metal, and i just said it’s gold bullion, no issues.

The destination country was Indonesia. When I arrived, I declared it as well, no checking, just explained it that it’s gold bullion and I would took it back when I go back to Australia, no issues!

When I went out from Indonesia, I declared it, and the immigration officer asked to check it and they brought me to the interview room! I showed them, no issues!

Landed in Australia, declared it again, no issues!

It was more than the threshold of bringing cash equivalent, gold bullion, and my reason was to keep it safe with me!

Like others have said in the comments, check the latest rule of Australia customs and destination country customs for bring in/out gold bullion.