O(2 pack) Smart Plug with Energy Monitor, no hub required, work with Alexa [amazon.com]
$19.49 w/ Code: Q7SN977Z (35% off for each one)
This smart outlet is compatible with Amazon Alexa and works with Google Asistant (even if you don't have a Google Home device), you can control your devices using just your voice. It also can be controlled by IFTTT.
Energy monitor: check the real-time and historical power consumption of devices connected to the socket in phone,will help you choose energy-efficient devices.