The scope of their actions does not require them to have passed a driver's test.
so they can't induce movement of the vehicle, at all, ever?
that's probably fine then
but if they can at all: they need a driving license
it is not unreasonable for a state to want to control who is allowed to move around 1.5 tonnes of metal in a public environment
I'm skeptical of this. Something as simple as knowing the meaning of curb painting color, turning on red, or knowing when to move past an emergency or other special vehicle requires non-universal knowledge of regulations, sometimes hyper-local. The idea that nothing they do would be affected by country-specific regulations is dubious.