You need a special script for Argon One (the version with the installed IR) for usage with LibreElec. V2 of the board allows to power up the RPi4 with IR. Maybe this script helps:
the full installation script can be seen in this german article.
I am unsure this script is valid for librelec, as it does not require the sudo command.... I read the article and that code only mentions raspbian and ubuntu.