Syncthing is a continuous file synchronization program. It synchronizes files between two or more computers in real time, safely protected from prying eyes.
Your data is your data alone and you deserve to choose where it is stored, whether it is shared with some third party, and how it's transmitted over the internet.
Visit https://syncthing.net/ for more information, downloads and donations
in LineageOS i have the option to change language from "app info" and syncthing-fork starts up with the chosen language.
I can't see any option to change it in the app except from the "Web GUI" (up right) which works only in the Web GUI (which may be enough for you)