I had the opportunity the other day to go for a little walk and I took along the Sony A7II with the Canon 40 f2.8 STM mounted via the Commlite EF - E mount adapter. I have now set back-button AF on all my Sony Alpha cameras but I just couldn't get this to work using the adapter. It's probably not supported so I used the top button in the usual way. Maybe someone out there knows more about this than I do. I would appreciate any feedback.
Light was not great, cloud cover with some haze. I expected better but I did my best. I can confirm that AF is ok but not great. Image quality is good to excellent at all apertures but I tend to use between f2.8 and f5.6. Images were lacking in contrast and colour was a little low. Being a raw only shooter that didn't bother me as it gave me some more leeway in PP anyway. If your a jpg shooter you may want to check your setting if using this combination.
Following are some test images taken during my walk. All have been processed to my taste.