LevelSpeech2.ny … Improved "leveling" for speech - #27 by Trebor
IMO it’s better than Audacity’s native compressor for speech.
Apply any noise reduction before using LevelSpeech2, or other compression.
Split stereo to mono, then delete the unwanted track …
https://manual.audacityteam.org/man/splitting_and_joining_stereo_tracks.html