Hi thank you so much for the reply, and sorry for the delayed response from me.
Your first point is right, that I often connect to various networks, and hence only wanted auto-update to work on my home network (wired/wireless). I often use public wifi or my mobile hotspot, so just don't want auto-update to work on those networks.
Today there are so many launchers on PC that it's quite laborious to manually update games every time you want to launch them, and quite a bummer too when there are sudden large updates waiting.
I thought of making a script too, but I am more of a hardware guy than software, and navigating through the DRM techniques used by these distributors seems near impossible to me,
For now, I have moved all games to my external SSD, as it also keeps me from the temptation of playing games all the time. And I launch all launchers every time I am home and SSD plugged in. A caveman solution and still not automatic but working so far 😁.