

I got the notification for the update right before the OS update, but I updated OS first and Logitech Options later. Logitech Options download page says that the current version 7.14.77 works on Mac OS X 10.14.x, so it seems like it's supposed to be compatible, though the last release was before the launch of 10.14.6 on. (oops I replied to myself, I meant to reply to you have Logitech Options installed? I also have it and I was wondering if it's the thing that causing the trouble. Resign that I'll never be able to use an external keyboard that isn't made by Apple? Wait for a firmware update from these keyboard manufacturers?

If I had to guess, I think this is maybe due to a recent change in 10.4.5 Mojave: Disables accessories with insecure Bluetooth connections.

Checked that the batteries the keyboards are healthy and there is no interference (like I said, they work on other PCs).Resetting bluetooth to factory defaults (Debug > Factory Reset.).I can see the keyboard in the Bluetooth window in OS X, but when I click " Connect" it rapidly flickers between " Connected/Not Connected" status and eventually disconnects. These keyboards work great via-bluetooth on the PCs I own, but they just won't pair with any of the 4 Macs I tried them on (three 2019 Macbook Pros and one 2014 Macbook Air). I have 2 different bluetooth keyboards (Logitech Craft / Microsoft Surface).
