I read in documentation:
6. Smart Scene (Android)
This kind of scene is usually called smart scene. Users can set a data range as a condition to trigger ON/OFF other devices. You may set a specified temperature/humidity/light intensity/sound level range from Sonoff SC, Sonoff TH, S22, At Home/Away status from Nest or RF Bridge’s alarm message as a condition to trigger on/off one or more smart devices under your account.
But I can't find any "home/away" option in ewelink 4.6.0 for android.