Global encoding settings in the GUI

[stderr-to-devnull]

Is your feature request related to a problem? Please describe.
Encoding settings need to be modified for each video and are not remembered on next use

Describe the solution you'd like
Encoding settings should be made global so that they apply to all loaded videos

Describe alternatives you've considered
N/A

Additional context
N/A

[k4yt3x]

You can add multiple videos at once and the settings will be applied to all videos. For saving encoding settings, that's tracked in #1290