I currently have a Xiaomi Aqara Zigbee gateway with Xiaomi movement sensors and smart buttons. There doesn’t seem to be an easy way to get this setup to operate my Sonoff & TP-Link switches so I am thinking of ditching the Xiaomi gateway and replacing it with a Smartthings hub which I understand is compatible with the Xiaomi sensors & buttons. I have Amazon Alexa and Google Assistant set up to operate the Sonoff & TP-Link switches. Will it be possible to use the Smartthings hub to trigger the Sonoff & TP-Link switches when the movement sensors or smart buttons are activated? Would IFTTT be one option?
There is a cloud to cloud integration that will allow you to control tp-link devices via smartthings. I’m not sure about Sonoff though. You’d need to search the forum to see about that. But if so, then everything you want could be configured in Smartthings.
Another option might be to use Alexa Routines to detect the aqara sensor that is connected to Smartthings and then control the non Smartthing devices like TP-link. This should work along as you have the Smartthings Skill and TP-Link skill installed on Alexa. You would also need Sonoff to have an Alexa skill installed and the skill would need to make the sonoff devices appear as smarthome device in Alexa. (I just don’t know if sonoff offers this.)