I used this (fbs) once for one of my early projects. A few notes that I remember:

- fbs was built ~2017

- to use Python 3.7+, PyQt6, or code signing, you need the paid version. The free version limits you to Python 3.6 and PyQt5.

- the main command is fbs freeze, which builds an executable

- fbs requires a couple changes to your project structure and main.py, compared to the default PyQt way