That’s not really using the Earth’s rotation to generate power, it is just a roundabout way of converting rocket fuel into electricity.
The generator poles thing would probably need to be installed at both poles and then attached to the counterweight orbiting the equator to avoid pulling it out of alignment. Like the Earth is playing a perpetual massive scale game of jump rope. It’s not much less practical than the original proposal, but only because it is hard to come up with something less practical than the original suggestion. 
