For those wondering how to quickly export a folder from stereo to mono WAV files with Audacity. Takes about 5 seconds for a big folder here with 125 files.
With Audacity open >
Tools >
Macro Manager
Make a new macro > click
new, give it a name
Click
Insert > Stereo To Mono (shown on image above and below)
Insert > Export as Wav after this step. Without that, it will not save anything automatically.
The above is what a basic batch with tasks should look like before you save and apply it.
When done, hit
Save and close the window.
Handy for all times you need it again in the future.
Now the batch processing:
To start:
Tools >
Macro Manager > select
stereo to mono and on the bottom hit the
Files button and select all the audio files.
Once you hit open, the batch will work and export them to C:\Users\
YOURUSERNAME\Documents\Audacity\macro-output
Just dropping it here so it's a more universal topic for those interested in another option (You can extend the macros and even apply fx).