Is there a way to restore my settings without redoing everything manually?
The "problem" with SDcards is that they are can be quite vulnerable. But power failure itself should not damage the SDcard unless Kodi was in the process of writing something to the SDcard at the time. But to answer your question: yes, there is a way. It's called restoring a backup, which unfortunately not everyone in computerland has always time for. They only find that out, after disaster has struck.
With power failures, it's impossible to know from the outside which part(s) are or aren't broken. Something in Kodi's databases can cause corruption which you only find out later.
if you can SSH into the RPi, and rename the .kodi/userdata/addon_data/service.libreelec.settings/oe_settings.xml file to something else temporary, and reboot LE, that should reset something.
Alternatively, take the SDcard out the RPi and place it in a PC.
Run a Linux Live distro such as Ubuntu (which can read EXT4 partitions), and copy/edit the necessary file(s).
Thank you. I finally got some time to do it. 
The initial oe_settings.xml file was corrupted and unable to be read. I moved it and the rpi started with a proper installation but I needed to set everything again.
