This actually seems fairly easy to do, and if you want, I could even find the time to make this replace the 84e (grenadier company), 15eme (light company), and the 45e (line company) with their associated companies. Could even change the sappers too. However, it would take a considerable amount of time longer... I could even replace just the Polish Legion too, if that's really all you want. Not sure when I'd be able to start work on it, but it seems like a fun project.