Hmmm, allow me to comment?
France did use Blue for most of that period, but pre-napoleonic wars under the bourbons their armies mostly used white uniforms. Beyond this comment you have to presume you are talking about the bulk of the foot soldiers right?

In that case your assumptions would seem accurate.
During the Napoleonic wars the Swedish used Blue edged with yellow. Spain is a difficult one to judge, they seem to have began using white before adoping other colours as the war went on, and given their nature of government at the time determining any one colour was hard. Italian states varied as did the german ones to a greater extent due to their origins being seperate armies to begin with. Dutch-Belgians mostly used blue throughout the wars and so on.
This obviously though would still lead to confusion on the field of battle. At Madia for example the French deployed a swiss regiment which were using Red uniforms as was traditional for them only to be shot at in confusion by their fellows thinking they were British! Napoleon also made an error at Borodino which angered his Saxon allies when he refused to acknowledge their achievements. The Saxon Gardes de Corps (in white) were the first to storm the Raevsky redoubt followed by the Polish and Westphalians curassiers in blue. Berthier said "The Saxon Cuirassiers are inside!" , but Napoleon being Napoleon saw those behind and seeing as how the French Cuirassier dressed also in blue declared "they must be
my cuirassiers.
Interesting fact, in "german" states you probably mean the confederation of the Rhine right? Well the confederation of the Rhine seemed to have problems with geography back then. Either that or the Duchy of Warsaw was a hell of a lot larger than Poland is
The point I guess I'm loosely and vaguely making is that each army had it's own regiments that did not conform to the normal uniform of the country, be that the Rifles of the British army or the Swiss regiments in the French. Cavalry and so on though are another issue entirely

Just imagine what a multi-coloured mob Napoleon's army of 1812 would have been
