Shutter releases on the A7 line from Sony actually uses something that is called a MULTI port. It is not a USB-C port. Most of the A7 line now has USB C ports as well.
We support shot triggering from the eMotimo ST4's camera port using the CL-S2 variant of our shutter cables. https://emotimo.com/products/camera-shutter-cable?variant=399323987995
Known cameras that use the multiport are A7R, A7R2, A7R3, A7S, A7S2, A7S3 and likely any new variant in the Sony Alpha line.