No, it not working in any zoom (1.4x and etc.) In addition, second camera is never used in auto mode because of bug in kernel.
And if you try to record slow motion video, main camera have 1.5x zoom for some reason with ois....
Xiaomi Mi6
7.9.14
1) Battery drain while camera app launched in background.
2) Slightly different vibrate power in default/silent modes.
3) Camera ois is not working in zoom ( works only in x1.0 and manual mode)