As said before: Jägers on Austrian army are Bohemians!
If you want do Bohemian, or moravian line regiment, there is nothing easier, than choose common infantry in game (I don't recall the name)
There were just slight changes in insignias for Czech regiments, AND officers were Austrians anyway! (Czechs were considered as best front line soliders not commanders [for high discipline, without lack of ability to improvise])
But I understand that it is unfair, because in most important battle Aus/Fr Austerlitz (aka Slavkov) was fought almost only Bohemians/Moravians... But history likes to forget contribution of minor nations
DanyEle: Don't be rude my friend... I wonder who from your Italian gang can speak decent English! -> You should bring them over to battlefield someday!