From November 2019, all new motorcycle models sold in Australia over 125cc must have ABS, while bikes with lower engine capacities must have either ABS or combined brakes systems (CBS).
The new Australian ABS regulations only affect new models made after that date.
All other existing models won’t need to be upgraded to ABS until November 2021.
(The laws only affect new motorcycles made after these dates. It is not retrospective.)
There are exemptions for enduro, trials bikes and trail bikes under 250cc.
If the bike has switchable ABS, the default setting when the bike is turned off and turned back on again will be for ABS to be active. We do not know of a motorcycle that allows ABS to switched off on the fly.