Quality settings

Lossless Copy needs matching codec, sample rate, and channel count, a container that can hold that codec, and no trim, gap, crossfade, fade, or loudness change. For bitrate formats, the source bitrate also has to sit close to the bitrate you asked for.

Loudness targets run from -24 to -5 LUFS. The default is -14, measured on the finished file, not on each clip. Fades are 0.1 to 20 seconds at the very start and end of that file.