Today Nikon announced the cheapest Z camera in their range: the $1399 Nikon Z5. You can see a full spec comparison with the Sony A7II and A7III on that special BH comparison page. I don’t feel like Sony has to make a model to compete against it. The much cheaper A7II holds up well while the A7III has a BSI sensor (Z5 has not) faster frame rate (10fps vs 4.5fps) and definitely a much faster autofocus.
But there is one more Sony surprise:
If the rumors are true than Sony might announce a new sub $999 FF camera in late summer early autumn. But unlike the Z5 or A7 series it won’t have the EVF in the center and be smaller than all of them. But those are wild rumors for now and I hope to get more info about this camera after the Sony A7sIII announcement.