I know this is straying from the OP a bit but....
Today I did a quick and dirty comparison between the Z9/400 4.5/1.4x TC vs the A1/200-600@560mm. We had a moose cow lying in the back yard this evening. The light was failing and it was a high ISO situation so not ideal. But under the conditions the pre-edited results for all practical purposes were virtually identical. After running the images through DxO PL the shots with the A1 were clearly better. But... there is still no lens profile in PL for the 400 4.5. I tried to go back and run the A1 file back through PL with the lens corrections turned off but ran into technical problems and gave up
So went back to the RAW files and applied NR in LRC and then an identical level of sharpening to each. The results were pretty much a toss up.
This was by no means a "test". Conditions were not controlled at all. Shots were made with the same ss and f-stop, handheld w/VR on, and auto ISO. Just a quick practical comparison to see if there was an obvious difference in IQ. Nope