Other than changing the global language to French or English, each Client Application has a language parameter that can be defined on the application shortcut to change the user's language preference for DTA and Scribe Player.
The two languages supported are "en" and "fr" passed with the "-lang" parameter. When changed, the applications will be set in French or English accordingly.
Not setting this value will follow the global parameters which are usually defaulted to English.
French
"C:\Program Files (x86)\Sliq\ScribeHansard\ScribePlayer.exe" -lang fr
"C:\Program Files (x86)\Sliq\ScribeDesktopAssistantV5\WorkflowDesktop.exe" -lang fr