I agree this configuration won't sound like a Leslie but the doppler effect will be present and audible in some fashion. I imagine a stereo pair of directional mics pointed at the baffle offset from center would pickup lots of frequency shift, it might sound cool or stupid but it would be audible.
To really understand-you have to go back in time a bit. Why was the rotationg Leslie developed?
One reason was to try to simulate a large pipe organ in a reverberant room. In that situation-there is sound coming at you from all directions-AROUND the room.
So by leaving the drivers stationary and using rotating horns in the horizontal plane-the sound would tend to bounce around the room and as the angle of the horn changed-the angle of the reflection would also change-giving it the "swirling" sound.
When they were developed-I am sure miking it did not even occur-since you simply didn't do that back then.
I still hold that while you would appear to get "some movement"-it is nothing like loudspeaker rotating in the horizontal plane. At least the ones I have heard. It would lack the "envelopement".