Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.
Since python-uharfbuzz links the system harfbuzz package and does not bundle code from harfbuzz, there is nothing to be done in python-uharfbuzz. If the fix is backported to the harfbuzz package in Fedora 42, then python-uharfbuzz will benefit as well.