Works!!
RPI5 - with Libreelec LibreELEC-RPi5.aarch64-12.0.1.img.gz
What I did:
Create the file em28xx.conf in /storage/.config/modprobe.d/
add blacklist em28xx in that file. (not module_blacklist=em28xx like in this post)
Thats it.
Without that file dmesg is:
https://paste.libreelec.tv/honest-flounder.log
with em28xx.conf:
https://paste.libreelec.tv/adapting-doe.log
Also I have a TX3 SS905X3 TV Box with the LibreELEC-AMLGX.aarch64-12.0.1-box.img.gz image. (sm1 X96 Air dtb I think)
Works without creating the em28xx.conf file.