I've successfully flashed the FACES-Firmware, using this command line

esptool.py --chip esp32 --port /dev/ttyUSB0 --baud 460800 write_flash -z 0x1000 ./m5stack-micropython-tft-repl-v1.0.bin

After this, I got this prompt:

The OSError is due to a missing main.py. After adding this with mu-edit, the error no longer occurs.

The REPL is also available on the serial interfaces, accessing it with tio /dev/ttyUSB0

Wow! I was looking for a pocket calculator for my twelve year old. I had an m5stack faces laying around, flashed with RunCPM, but unusable for me because of the tiny font it uses.

So, thank you for making this available.