Yes. For a typical 1 HP motor at 230 volts, the motor draws 8 amps. The secondary of the transformer must pass this 8 amps, so the primary will draw .8 amps (using the typical 10% boost, a 240 to 24 volt transformer as an example). So the current from the "panel" is 8.8 amps. Which, by the way, is the typical design current for a 1 HP motor on 208 volts.
This is why I said the primary leads of the transformer can use smaller wire, but not any wires feeding from the source to the secondary or motor! So, unless the primary is fed separate from the motor wiring, no, same size wire. And the OCP would be the same rating. The overload setting would change depending on if it was before or after the transformer.