Some french ancien régime uniforms i found.
The two first plate show typical french line infantry uniforms of the era with a greyish/white coat and colored facings and vests.
The drummers (with a few exceptions) wear the royal "livrée" iirc.
The "gendarmes" (men-at-arms) of the other plates however should not be confused with the "gendarmerie" who assured order in the rural areas of the kingdom, these ones are the inheritors of the formers "compagnie d'ordonances" of the late medieval era and constitute heavy cavalry. They may even be reserved to the nobility, although i am not sure about that.
EDIT
Or maybe THEY are the "gendarmerie" unlike the "gendarmes" of the others plates...
I am not quite sure there.
Yet, another typicals french line infantry uniforms.
The drummer wear a different uniforms than the one of the previous plates because his regiment was (or is, at least theorically) owned by the queen.
The other regiment is the property of the king (wich mean its colonel should be the king himself and the actual commander is just "lieutenant colonel") wich is why there is "royal" in his name (obviously) and why there are lilies on the white cross.
The white flag is the Bourbon's dynasty flag, the lilies are the symbols of the king of france and the white cross present on most french regimental flags is typical of the french army since the hundred years war (wich started with the french wearing red cross and the english white ones and ended the other way around :hmmm
Those plates show the household troops.
First the infantry, with the french guards, recruited among french commoners to guard the entries of the royal palaces and other important places and the swiss guards (recruited among, swiss, surprisingly enough.
), those two regiments constitutes both at the same time a ceremonial unit and a military one, often deployed in the field.
The grenadiers are a kind of multipurpose unit, second only to the bodyguards in the honorifical hierarchy of the french army, able to fight mounted, on foot, to do engineer style works, guard the king etc.
I have nothing of note to say about the "light horse" however excepted that they were "light" in the medieval era, compared to the "gendarmes", they aren't a real light cavalry unit.
Yet another series of plates about the royal household troops.
This time they are cermonial units however.
(Although the bodyguards and musketeers could be deployed as heavy cavalry in the field from time to time).
The hundred swiss guard the king's appartments and other important places and some of them are always following him wherever he goes.
The bodyguards (or lifeguards) are composed only of nobles and are the most senior unit of the french army and of the household troops.
Their closeness with the king and their recruitment explain this position.
The musketeers are recruited among the lesser nobility or cadets and often constitute the entry into a military career since serving some time under arms is required to advance, they chose to serve in an elite and honorific unit (although a junior one compared to the bodyguards).
The household again, this time the one of Louis XVI toward the end of the ETW timeframe.
Notice the black musician of the french guards.
Because of the french west indies and slave trading, blacks weren't totally unheard of in metropolitan france by the end of the XVIIIth century, despite the fact that the "code noir" (black code, the corpus of laws regarding slave ownership, relations between master and slave and freed slaves) forbade the ownership of slaves in France proper...
As freed slaves were considered (theorically at least) as normal french citizen, some of them served in the navy or the army, others came to work in France and some were recruited as "exotic" servants by the upper classes.
There was even at least one black colonel iirc (although in his case, being in the entourage of the king, paternalism and the spice of exotism played probably more in his nomination than anything else)
Two others line regiments but this time their gear might indicate that they are deployed in north america (especially the axe/tomahawk or the summer/fatigue dress of the soldiers of the Sarre regiment)
The last plates are about french units of the AWI, including one of the irish regiment in french service (who wear redcoats like the british infantry).
I have no idea about what is the "royal deux ponts" (royal two bridge ?), maybe a unit composed of former sailors or naval infantry ?
If people are interested i have other plates.