This isn't strictly true. She can't do this in the UK, so she won't be able to do so in Australia. As much as I dislike the Royal Family, they have very little power. It's mostly symbolic.

See here:

https://www.aph.gov.au/About_Parliament/House_of_Representatives/Powers_practice_and_procedure/Practice7/HTML/Chapter1/Powers_and_Functions_of_the_Governor-General