This video covers the steps involved in changing the firmware, on a FrSky X-Lite, from EU LBT to Universal. The steps are correct as on the date of recording.
The ZIP file, mentioned in the video, can be found here https://drive.google.com/file/d/1vyFiyvDsfHfXGdLbp-Fag-oogGwjXWtU/view?usp=sharing