The Language isn't the firmware change, its just a setting.
System Settings > Common Settings > Screen Defaults > Default language = Russian
Thank you for using the Support Forum. Please take a look at the support pages for your printer on the Russian language Xerox site. If you do not find the firmware there please contact your local support centre.
Hello. Sorry for my bad english. Requires firmware on WorkCentre M123 with Russian language. The employees of my company do not know English, so I need to update the firmware of the device. Maybe someone has it? I will be very grateful