There’s also the Palatinate branch of the Habsburgs, the ones who served as Palatines governors to HungaryHe is Archduke Karl of Austria, Prince of Hungary, though I don't think he has ever made any claim to any throne.
Archduke Karl is the eldest son of the late Archduke Otto, Crown Prince of Austria and of Hungary, himself the eldest son of the last Emperor of Austria and King of Hungary Karl I.
https://en.wikipedia.org/wiki/EsterházyThe House of Esterházy, also spelled Eszterházy (Hungarian pronunciation: is a Hungarian noble family with origins in the Middle Ages. From the 17th century, the Esterházys were the greatest landowner magnates of the Kingdom of Hungary, during the time that it was part of the Habsburg monarchy and later Austria-Hungary. During the history of the Habsburg empire, the Esterházy family was consistently loyal to the Habsburg rulers. The Esterházys received the title of Graf (Count) in 1626, and the Forchtenstein line received the title of Fürst (Prince) from the Holy Roman Emperor in 1712.
Gloria von Thurn und Taxis is a descendant of this family too. The family has ties with the aristocracy in the U.K too, related to the Earls of Jersey.