Yes, screwdrive A-mount lenses work with the Sony LA-EA5 adapter on the Alpha 7C. The LA-EA5 adapter supports autofocus with 2nd generation Sony screw drive lenses by using a screw drive focus mechanism powered by the camera body. This allows autofocus functionality for these lenses on compatible E-mount cameras like the Alpha 7C, similar to how it works on models such as the A7R IV and A6600. However, autofocus performance may not be as fast as native FE lenses but is functional for still photography.