I was recently informed about LSC Smart Connect 3 door sensor selling on Action discounter with over 600 stores across the Netherlands, Belgium, France, Germany, Luxembourg, Austria, and Poland.
The door sensor is based on ESP8266, and people have bought a few and flashed their own open source firmware converting the device into a multi-purpose sensor device with ESPNOW protocol that enables direct and low-power control of Espressif devices without the need of a router.
The module inside the door sensor is called TYWE3S, which one document on the FCC website refers to as "Tuya WiFi module" and