You would be unwise to do so, one engine at high power is enough to put a lot of extra load on the tow bar with the potential to break the shear pins in the bar.
The result of this would be the aircraft propelling its self at high assymetric power towards a tractor also at high power going in the opposite direction, who knows which way the sheared tow bar would go !
The chances of one of the ground crew going into the engine are high and it is very likely the tractor driver would be crushed between the loose aircraft and the tractor.
And all this for what ? Saving a few seconds............ As I said a very unwise and unsafe idea.