Hi, this adapter is for Canon EOS mount lens to Sony E NEX mount camera, we checked the sony a 7iii camera mount is E mount , this adapter can fit it , but you can reconfirme it , thanks.  

So with my sigma 10 20, only a little with 11 mm but no longer visible with 12 mm (aps-c) 

Yes, it will fit any Sony e mount body, either full frame (a7..., a9...), or aps-c (like a6500, etc) 

FD-EOS fit for Canon FD mount lens and canon EF mount camera body. canon 60d is EF mount, so the adapter ring can work with your camera, but you need to check your lens mount. could you pls let us know your lens specific model? service(AT)kentfaith(DO NOT)com, Please note: It is not same between Canon FD mount and EF mount, this adapter ring is only for Canon FD mount lens, please contact us if you want to purchase for Canon EF mount lens. 

No, this adapter is for the older manual focus Minolta Rokkor MC and MD lenses. If you want to autofocus and aperture control you will need the Sony LA-EA4. (the lower cost Sony LA-EA3 will electronically connect A mount lenses but you will have to manually focus.)