ModuleNotFoundError

[brupelo]

ModuleNotFoundError

[xixixao]

You need to pass full file path to the --reload argument.

That said the current addon code uses exec, here's a better version using module loading:

dir = os.path.dirname(cmd)
if dir not in sys.path:
    sys.path.append(dir)
__import__(os.path.basename(os.path.splitext(cmd)[0])).main()

This allows you to import any blender module like bmesh.