If you want to know more about various countries and their e-bike regualtions look here (
https://en.wikipedia.org/wiki/Electric_bicycle_laws). You will see that Australia broadly follows the EU (250W maximum power, 25km/h maximum pedal assist, 6km/h maximum throttle speed), probably mainly to increase the availabiltiy of mass-produced bikes that do not require significant alteration. SmartMotion bikes though, for example, are from New Zealand where the regulations are significantly different, especially in terms of power output, maximum speed and throttle use. With some makes it is a relatively straightforward exercise to "convert" them back to their original set up (or at least partly) provided the bike is to be used in an "off-road" situation.