Temperature sensors with WiFi for remote control - Xiaomi/Mijia, Sonoff/Zigbee

Hello
I'm looking for temperature sensors to control the temperature when I'm away from home.
I was thinking of Xiaomi/Mijia,but they seem to work only with bluetooth,so out of the house lame...
For the moment the only thing that makes sense I found is to play with the gateway zigbee and under it connect the temperature sensors. I will not say because it is cool (setting up scenes, etc), but for me it is mainly about temperature control. Nothing else.
Will I find something interesting, or is there only Sonof/Zigbee and play with the gateway and sensors?
If I have chosen the wrong section, please move it.

Possibly a reworking of the sonoff with supla, tamosa, domotowicz, etc.

I own a Sonoff, I can't remember the model. I have installed it in the server room at the company, for now I am controlling the temperature with it, but I intend to switch on a second air conditioner if needed.
Recommend.

I recommend one like this:

https://itead.cc/product/sonoff-th-elite-smart-temperature-and-humidity-monitoring-switch/

I have an older version and it has been working without problems for probably 2 years.