I picked up my FE 90mm yesterday and am currently playing with it. So far, beautiful!
I had read Kevin's review months ago. Doing my initial testing I was perplexed that when I had the lens on the camera, the menu steady shot icon was greyed out (I have it in my Fn menu). I recalled reading his comment regarding OSS and the A7II's 5 Axis stabilization and re-read the review to confirm my understanding. Checking forum I didn't see any update from Kevin regarding his comment that he would follow up.
Taking a shot in the dark, I reached out to Brian Smith to ask how he thought it should work (yes that Brian Smith, Sony Artisan, award winning photographer and author of the Sony a7-Series: From Snapshots to Great Shots book).
I was specific that I was using an A7ii, not A7Rii, and the FE G 90mm Macro. I was quite surprised when he replied within an hour. FYI, here is his response:
"That setting is grayed out in the menu whenever you use a lens with the OSS switch in the lens because OSS is controlled by the switch - not the menu."
Thought I'd share,
Keith