It's low priority for me but I'm accepting PRs if anyone else wants to do it
I don't think that any supported device in LE is powered from battery... Anyway, even if crust gets supported, only button will work for turn off/on. IR and CEC are not supported in crust (yet?).
Honestly a way to power on/off without pulling the plug would be great. IR might have to wait a while longer but that's ok