I am cross posting a little form the issue reporting on GitLab. I have not had much luck there.
TL;DR: Please could support for the second camera (x2) on the Xiaomi MiA1 be added to the /e/OS.
So, bought a phone supported by /e/OS as you do 
Installed said OS after a very brief play with AndroidOne. Now, the x2 Optical Zoom was a good selling point for the Xiaomi MiA1 and worked great in the stock OS. In /e/ there is no option, what so ever, to activate it 
I understand /e/ is in beta, but if a phone is listed as “supported” then I feel all of the hardware on the phone needs to be supported otherwise that is more like alpha than beta.
Overall, quite happy with how the OS is functioning and I can’t wait to fully degoogle 