If I bought even a cheap anko charger from Kmart or any physical retailer in guessing it would be fully compliant with whatever safety regulation we have.
Is this the same as Amazon? Would they have some sort of standard about what can and can't be sold though them? If not wouldn't they'd be big enough to catch heat if a few of their products sold through them burn down somebody's house?
Anything sold directly by Amazon AU should be fairly safe. For anything else one takes one's chances.
The Amazon marketplace is full of dodgy sellers based in China and elsewhere. Amazon makes zero checks on the quality or regulatory compliance of this stuff.
And no, they won't "catch heat" any more than ebay will. Amazon will just claim that it's not them selling the product, it's a third party.
The best that you can say is that Amazon has very generous refund policies, although that won't be much comfort when your house burns down.
Still, I have a dozen little Amazon time bombs in drawers around the place just waiting to go off. No explosions yet. ;-)
I will say this, there's no guarantee of compliance at any standard Australian shopfront retailer either, including KMart, as you can tell from all the recall notices taped up around the entrances to just about every national supermarket and department store chain.
In Australia regulatory compliance is an honour system, and the solution if something goes wrong is to issue recall notices. See here, for example https://www.kmart.com.au/product-recall/ and here https://www.harveynorman.com.au/product-recall-notices and plenty of power banks and chargers here https://www.officeworks.com.au/information/policies/product-…
This is also Amazon's system https://www.amazon.com.au/your-product-safety-alerts (US site with the actual alerts https://www.amazon.com/product-safety-alerts )