I would start by submitting an issue on the Github of the plugin. The developer of the plugin is most likely to be able to help you. You can also see some errors from some plugins in KiCad settings, though I can’t remember where off the top of my head. Maybe Preferences > PCB Editor > Action Plugins?
I will mention that it is not obvious how to get to the Python version bundled with KiCad on Mac, which is the python version that needs pyparsing installed. For v7, the version is found here for a “normal” installation: /Applications/KiCad/KiCad.app/Contents/Frameworks/Python.framework/Versions/3.9/bin/python3.9
After you install with something like ``/Applications/KiCad/KiCad.app/Contents/Frameworks/Python.framework/Versions/3.9/bin/python3.9 -m pip install pyparsing`, you may need to re-sign the whole KiCad.app. The KiKit instructions may be useful to you in this process. macOS - KiKit — Automation for KiCAD