@MurzikYEET I think that you cannot do this if you want the firmware to run while the device is on. The way all computers work is they load the program into RAM and then run it from there. The firmware just tells the computer what to do (in this case, open boot the device and then run the python file).
I believe you can't flash two sets of firmware from M5Burner anyway because each time, it erases the whole device before starting again.
With esptool the same applies. It can't load firmware into the RAM. What it does do is load the stub loader which helps the device and esptool install faster.
However there is a way to do it. I myself am not familiar with it but I believe that you can create OTA slots that store firmware in different slots on the device and then you can boot into different firmware.
Here is documentation on OTA: Espressif Docs
Hope this helps,
RPi
