Domoticz

Is there a type of power switch wich is, out of the box compatible , with domoticz ( on mij synology NAS) , preferable with power meter.
I don't want to flash the device....

any advice is welcome

You could try tp-link HS100/HS110 smartplug with plugin https://github.com/lordzurp/domoticz-tplink-smartplug/

Edit: Also Shelly has smart plugs that can be controlled with the Shelly MQTT plugin (a little bit more work because you have to setup MQTT on your server)
https://github.com/enesbcs/Shelly_MQTT