I tried the other CoreOne mounts for the ubiquiti G3 Instant camera and wasn't really happy with any of them. They either had a chance of collision with the extruder or the mount was not secure due to no adjustability etc.
I took the magnetic corner plug from @Blue (https://www.printables.com/model/1266139-prusa-core-one-magnetic-corner-plugs) and the ball and socket from @mistertech on thingiverse (https://www.thingiverse.com/thing:1785190) and combined them. The ball was hollowed out to accept the screw from the OEM mount on the G3, and the socket was tightened so that the joint would stay fixed in place without te need for the lock nut. In order to be able to print everything without supports the socket threads in to the corner mount. You will need to thread it all the way in so that it is only about 1mm from flush with the back side of the mount in order to achieve clearance with the extruder.
This mount is nice and secure and does allow for some adjustability of the camera angle.
Base is included with 20x7x2 magnet recesses and with no recesses if you want to use some other size that you have on hand.
Everything prints with no supports. I printed with PETG and did not need a brim on anything.
The author marked this model as their own original creation.