"Black Powder 2", like its predecessor, doesn't mess about in figure-to-man ratios. It takes the Featherstone approach of "that's a battalion", "that's a big battalion", and "that's a tiny battalion". It's much the same thing "Shako" does.
The closest it comes is when dealing with very small and very large units where it acknowledges that something ought to be done to demonstrate a particular unit isn't "standard".
So, my infantry is here based 24 to the battalion, six bases, four on each, covering a scale 240mm frontage -- bog standard for BP. Cavalry is two to a base, six bases for a 300mm frontage. There's a few larger regiments of cavalry out there -- the Dutch were huge -- and one of the Highland battalions is judged "small".