Canon EOS 6D Mark II Instruction Manual page 335

k Shooting Movies
When the [z4: AF method] is [Smooth zone] or [Live 1-point AF], you
can press the <B> button to display the electronic level (p.80).
You can set what is displayed for when you press the <B> button
(p.298).
If [z4: AF method] is set to [u+Tracking] or if the camera is
connected to a TV set with an HDMI cable, the electronic level cannot be
displayed.
The electronic level, grid lines, or histogram cannot be displayed during
movie shooting. (The display will disappear when you start shooting a
movie.)
When movie shooting starts, the movie shooting remaining time will
change to the elapsed time.
335