So, of course I had to do this comparison. 
I got me a little bit more darkness and made a similar test for the Sony A7 iv (with the Sigma 28-70 / F2.8), the Canon EOS 80D and 50D (both with Sigma 17-50 / F2.8).
At this point its probably tiring for most people, but I’m dumping my result here anyways - perhaps someone out there is interested… 
As above I tried to do a fair comparison with regards to field of view, depth of focus and ISO Settings (== equal shot), using the formulas in the above referenced article.
So the columns should be comparable regarding their settings (I think) and the rows contain the A7, the 80D and the 50D.
