Looks like there is a board with PIR sensor which is very useful.
http://www.electronics-lab.com/ttgo-t-c ... abilities/
https://www.cnx-software.com/2019/01/09 ... ir-sensor/
https://www.aliexpress.com/item/TTGO-T- ... 83765.html
I should say this particular model would be useful - if it didn't have unnecessary camera and oled screen which are increasing price a lot.
Is there maybe another model or something planned to be released just with PIR sensor?