One uniform I can answer is the British Grenadier which seems to be a 42nd Royal Highland Regiment of Foot as the backpack says 42. While the mitre cap is accurate, the axe really isn't. They were usually equipped with musket, grenades, and maybe tomahawk. Grenadiers were the shock troops of early modern warfare.

The jacket is completely wrong, while Highland grenadier jackets were different they had different shoulder "wings" than depicted if at all. Most of the fringed epaulletes were for officers. They wouldn't have those type of gloves either that fit over the large cuffs of the jacket. In the north they were given mittens or wool gloves. The collar is too large and too red, the collar matched with the facings on the coat, which are missing. They had dark blue facings and collar.

The sporran is close, they were issued goat while some had plain leather. The 84th got raccoon sporrans for their duration. I assume they didn't even try to get the tartan correct as it's supposed to be black watch. Also, they wouldn't have been as tailored as they are depicted. Great plaids were issued early on but stopped after 1778 for the 42nd as it got too expensive. Many made them into trousers or breeches when they wore out. The kilt is missing the top "extra" that is usually brought to the shoulder and pinned with a brooch.

Boots? Hardly. They were issued buckled shoes and hose.

Gallery of re-enactors as Highland grenadier

The mitre cap made it easier to throw grenades as the tricorn was likely to impede a good throw. Even with bonnets, Highland grenadiers wore mitre caps to show they were part of the elite assault troops. Grenadiers were imposing and tough soldiers.

Source: I'm a re-enactor for a Highland Regiment for the Rev War.

The French Revolutionary uniforms above have no relation to reality at all, apart from the outfits being clothes. French National Guards were like the picture below, especially in Paris, which subsequently formed the model for the French army as a whole. Here is a contemporary painting of a National Guard Officer (Lafayette) https://upload.wikimedia.org/wikipedia/commons/3/34/Serment_de_La_Fayette_IMG_2377.JPG I'm not sure of what the "extremist rebels" are supposed to represent, and as the Sans Culottes didn't wear uniform I won't comment. The Swiss Guard wore conventional French infantry uniform, but in red. These are near contemporary paintings that shows them http://brattleborohistory.com/images/Jean%20Duplessis%20Bertaux,%20Detail,%20Prise%20Du%20Palais%20Des%20Tuileries.jpg https://upload.wikimedia.org/wikipedia/commons/5/56/Jacques_Bertaux_-Prise_du_palais_des_Tuileries-_1793.jpg The latter also shows National Guardsmen.

I'm afraid that I can't open the American Revolution links, so can't comment on them.

Spanish uniforms in Florida would have been rather like these https://s-media-cache-ak0.pinimg.com/736x/a6/0a/2f/a60a2f3b30926df5ac44f282295758a5.jpg The dragoon, a cavalry trooper, would wear a similar uniform, with boots, but in a yellow coat. https://s-media-cache-ak0.pinimg.com/236x/a8/e2/db/a8e2dbac30cd3202f3e7f3d8ed52505f.jpg Contemporary picture here http://4.bp.blogspot.com/-uldbBNI1jVk/UkhJCmbDaeI/AAAAAAABQbw/9vTO9L_n3LM/s1600/HISTORIA+ORGANICA+N%C2%BA+40008.jpg

Contemporary picture of Hessian Jager http://www.jaegerkorps.org/www.jaegerkorps.org/Images/Jaegerwatercolour.jpg They weren't "bounty hunters" but regularly trained and officered rifle armed light infantry.

The British Revolutionary War Grenadier is actually a Sapper, hence the beard and large axe.

The Byzantine Almogavars (various spellings) were Catalan mercenary light infantry, who used a variety of spears and javelins, usually wore no armour, and also had a longish knife. Contemporary picture here http://www.catalonian-airlines.cat/files/images/almogavers.jpg