see picture how to serial connect https://github.com/arendst/Sonoff-Tasmota/wiki/BlitzWolf-SHP6
If you want to put micropython then this is the trick ( -fm dout) to flash:
esptool.py --port /dev/ttyUSB0 erase_flash
esptool.py --port /dev/ttyUSB0 --baud 460800 write_flash --flash_size=detect -fm dout 0 esp8266-20190125-v1.10.bin
after flash you can connect to serial terminal.