Using arduino-cli, the arduino-ide, or directly the esptool.py (from https://github.com/espressif/esptool) I obtain the following error when uploading a simple (correct) sketch.
x@y:~/blink$ ~/tools/arduino-cli upload -p /dev/ttyUSB0 --fqbn esp8266:esp8266:nodemcuv2
esptool.py v3.1
Serial port /dev/ttyUSB0
Connecting........_____....._____....._____....._____....._____....._____....._____
Traceback (most recent call last):
File "/home/x/.arduino15/packages/esp8266/hardware/esp8266/3.0.2/tools/upload.py", line 66, in <module>
esptool.main(cmdline)
File "/home/x/.arduino15/packages/esp8266/hardware/esp8266/3.0.2/tools/esptool/esptool.py", line 4074, in main
esp = esp or get_default_connected_device(ser_list, port=args.port, connect_attempts=args.connect_attempts,
File "/home/x/.arduino15/packages/esp8266/hardware/esp8266/3.0.2/tools/esptool/esptool.py", line 121, in get_default_connected_device
_esp.connect(before, connect_attempts)
File "/home/x/.arduino15/packages/esp8266/hardware/esp8266/3.0.2/tools/esptool/esptool.py", line 639, in connect
raise FatalError('Failed to connect to %s: %s' % (self.CHIP_NAME, last_error))
esptool.FatalError: Failed to connect to ESP8266: Timed out waiting for packet header
Error during Upload: Failed uploading: uploading error: exit status 1
esptool.py v3.1