@arcuza hi, you can add this configuration to config.txt:
hdmi_ignore_cec=1

Source: https://www.raspberrypi.org/documentation/configuration/config-txt/video.md

Normally the Pi should switch to composite if the HDMI port is not connected, but you can force PAL by adding sdtv_mode=2 to the config.txt configuration file.
Assuming your composite cable is correct and you've switched the TV input to the RCA input, you should get an image.

@bc320 said in Pi4 and libreELEC:

Is there a way to set up my pi so when I boot I can choose LibreElec and Kodi OR Retropie?

Using something like NOOBS or PINN could help you install multiple systems on the same sdcard.

is there an easy way to move between the 2?

Apart from using separate cards, try option 1.

if I am able to get a wireless/bluetooth controller to work with retropie will it work with LibreElec?

I don't know, if it has bluetooth support built in, then it should work.

@Hanky42 said in Retropie and Libreelec:

Wouldn't KODI want media added to it's library?

yes?

you add files to the library over network without moving the actual files or you can just play them directly from the source.

personally i use mysql (alltho a bit slow) to avoid having to recreate the library and remember which movies i watched on all devices using kodi in my home.

if you want something easier, you can look up plex media center, but i belive a "dedicated" server is required for that, i am unsure if it will run both a player and a server on one raspberry.

Powerblock works fine on Retropie/Raspbian. Open/LibreELEC are embedded systems so if it doesnt work OOTB, it is generaly a pain in the ass to make it work. The support for it should be given by them if they are interested.