Have anyone an idea how I can set the energysave (I dont know thats right im german -Energiesparen-) settings in Settings->Energysave and activate the suspend mode? I cant set this because its grey.
Try
[8.2.1.2] LibreELEC 8.2 for S912
But it is considered unreliable, with different results on different devices. Some not properly waking up anymore. Hence it being disabled by default. If you break your system you get to keep both halves.