You’ll need to provide some environment variables to the command line. Note: The example in that particular post is from Windows, so the environment variable will be different.
I’m curious what you’re attempting to accomplish though. Running it manually will not actually modify the file to remove commercials, nor will it update Plex’s database with commercial markers for the file. It will just produce and EDL file and some logging.
When Plex performs commercial skipping after recording, it runs its commercial skipper and then performs additional post-processing using the created EDL file. I’ve not seen anyone reproduce that step of the process directly from the command-line.
You can configure Plex to go back and run its commercial removal/marking process on existing media files; the configuration requirements are described in the post I linked. Just keep in mind that a DVR must be configured in Plex for this to work.
