I made a simple audio project with m4a and mp3 files.
Apply the compressor filter to the A1 track. The settings responded as expected (you can see how the Gain Reduction meter is reacting when I play the track)
The export (Youtube video profile) did not produce any crunching or additional problems.
I also did a test with the normalizing filter 1 pass.
I made some adjustments to make the operation evident (low target sonority and a wide measurement range or analysis window). As in the previous case, the Gain Reduction meter is working. No problem in exporting with the same Youtube profile.
In the animated GIFs, you can see that I used clips with different input loudness (which require more volume reduction.
Although the A2 track is muted, before export I enable it and the audio worked fine.