per default the plugin uses the english language file located in your ZenCart directory, here: ./includes/languages/english/extra_definitions/oneallsociallogin.php
Please copy the oneallsociallogin.php file to the language folder that you are currently using: ./includes/[ REPLACE BY YOUR LANGUAGE FOLDER]/english/extra_definitions/oneallsociallogin.php
Answers
no, you should be good now
Best Regards,