That file is obsolete... it's the qa-badge-lang-default.php that you need. It's not clear whether you should add files to the qa-lang dir, or just to the plugin dir iteself. It looks like the latter, which means just create a file like qa-badge-lang-fr.php for French.
Welcome to the Q&A site for Question2Answer.
If you have a question about Q2A, please ask here, in English.
To report a bug, please create a new issue on Github or ask a question here with the bug tag.
If you just want to try Q2A, please use the demo site.
July 25th, 2023: Q2A 1.8.8 released!