Actually I expected a lot of software update for A7iv due to his great (?) hardware power abled to be developed (such as for A1, also if I don't have but it's the reference of what sony can do with his platform).
In the real world no new function or really better function has come. The only "main update" is just for the creator app's compatibility (I found a lot of differences on the usability of the "standard" functions of the camera, not all in the better direction, but it's only my opinion).
At this point, with an hardware 2 years old, I'm not sure that Sony is developping any more A7iv. Maybe that a A7v (to be competitive with R6 and Z8) is coming.
So, also if your question is a little bit hard to answer, my opinion is "not, focus stack and pixel shift probably are reserved to "R" line in this moment"
