Sorry for that, but Batocera seems to be an edge case. Like LibreELEC, it’s not based on a main stream OS distribution, so I currently doesn’t expect that there already exists a working script.
May be this could be an option, if version 0.5 is released:
If the used kernel of Batocera a recent one and the dtoverlay is available, than you can also disconnect the fan from the case pcb and connect directly to the RPi5 board:
LibreELEC could be more widespread (in my opinion) than Batocera, that is the reason why there exist a Addon for that. But please doesn’t use the outdated version 0.0.1 (a.k.a. ArgonRemote.zip). You should install version 0.0.13, (or 0.0.12a, until I have released a bugfixed version of 0.0.13)