Shotcut is a video editor and… well, thatâ€™s it mostly, it allows you to edit videos and the UI is available in Gaelic. You can download the (free) program here.
If you have a Gaelic operating system, it will appear in Gaelic automatically. If not, visit Settings:
And pick Gaelic:
Youâ€™ll have to restart but thatâ€™s it!