Actually, now that I read this, I remembered I don’t use full microG right now 
I just use the standalone microG UnifiedNLP for a faster location fix (offline backend)
So I guess the best approach for me is to get the official LOS17.1 as soon as it’s available and install UnifiedNLP (No GApps) on that.
I’ve seen this howto and an older FP forum topic about this.
Anyone knows whether this adb method is still necessary for system registration, or does the current 17.1 build support UnifiedNLP installation in userspace from F-Droid?