I'm not sure about this period, but by the mid-18th Century all Austrian Dragoon regiments included a company (i.e. half-squadron) of bearskin-wearing Horse Grenadiers. These were then usually massed together on campaign (together with the Carabinier companies of the Cuirassier regiments) as an elite cavalry brigade.
Some other states (Wuerttemberg and Pfalz spring to mind) had Horse Grenadiers as part of their Dragoon regiments.
Horse grenadier companies were only added to Austrian dragoon regiments in 1713, which means they saw no action to speak of during the WSS. The Ebor figures are almost certainly intended to be Bavarian horse grenadiers : the Bavarian guard cavalry fielded one squadron of them (around 120 men) along with the Hartschiere and carabiniers and all three squadrons fought as a
de facto auxiliary cavalry brigade in the French army after Blenheim.
According to August Kühn, Holstein-Gottorp also had two dragoon units in bearskins : Colonel Von Dernath's Dragonergarde Regiment, who wore red coats faced red with white buttonhole lace (blue coats faced blue while on campaign), and the Baudisson (or Baudissin) dragoon regiment which had indigo blue coats. The bearskin cap was brown fur for the Dragoon guards - and apparently identical for Baudisson as well, though other sources despict the unit in tricorns (
http://www.baccus6mm.com/_paintingguides/WSS_Reichs.pdf).
Not sure the four Palatine dragoon regiments had grenadiers yet during the WSS : Kühn does not mention them so they may well have been a post-1714 addition.
Fiercekitty : Freikorps were not created until much later in the 18th century, so are not relevant for the WSS.