I successfully flashed this device using both Tuya Convert snd serial flashing soldering cables directly onto the TYWE3S chip. I would recommend the serial flashing method which also allows you to configure the setup without worrying about the chip going to sleep.
If configuring using the battery, 3 presses within 2 seconds energise the TYWE3S for about 50 seconds.
After initial setup type the following into the Tasmota console window:
Rule1 ON TuyaReceived#data=55AA000000010101 DO POWER ON ENDON
Enable the rule:
This device on Tasmota 8.2 does not report a full TuyaMCU message, but it sends
55AA000000010101 when smoke is detected.
I am powering this device using a PoE connection linked to a DC-DC step down PCB which fits nicely in place of the 2xAA batteries. I have soldered a cable between the power and the VCC of the TYWE3S which keep the Tasmote interface permanently available and allows simple resetting of the smoke detector after an activation.