It depends what you want to uninstall, you can either uninstall specific source, addons, etc..
Alternatively I once used an add on, that gives you a clean start, and restores Kodi to how it was originally installed, allowing you to start from scratch.
I can't remember which one I used but try an internet search for how to do a fresh start, on VU+, or an Enigma2 receiver.
Code:
https://www.youtube.com/watch?v=-zPJMcWltWY
Code:
https://www.youtube.com/watch?v=qTVoSfLu-dk
Code:
https://www.youtube.com/watch?v=5A4gdtYGKpo