This sub-dial has separate photo, video and S&Q ... and full-frame sensor in a newer model, check out the Sony A7C II which is a similar price to the A7 IV.

Putting a potential Sony A1 II to one side ... For us, the model that would make the most sense for later this year is a Sony A7 V, to sit below the Sony A7R V. Now that's a camera we'd be ...