[tinpanalley]

I have a 5.1 receiver that can no longer output the center channel.
But I want to watch 5.1 films on my system nevertheless even if the center channel gets mixed to the left and right front speakers.
Can I make Kodi do that for me on my Libreelec Rpi4 install?

[DaVu]

You should be able to configure your AVR to ignore the center-channel. Most likely every AVR out there from the last 15 years is able to do that. There's no need for Kodi doing that if the problem can be solved by the device which is processing the signal.