Game concept
Vassal Stance
The game also links it as Vassal Stances, Preferred Heir, Unpreferred Heir, Preferred Heirs, Unpreferred Heirs.
From the game's encyclopedia
Every Vassal has a Vassal Stance which affects the Opinion they have with you as their Liege, and which Heir they prefer as successor to the Realm.
Vassals in the same stance will like and dislike the same things. For example; all Glory Hound Vassals dislike when you lose Wars.
Every Vassal Stance prefers one specific Heir. Upon succession, each preferred Heir will have lower Legitimacy Expectations with the Vassals of that stance.
The Vassal Stances are:
• Courtly
• Parochial
• Glory Hound
• Zealot
• Minority
• Minor Landholder
• Belligerent
The game's text for patch 1.20.1.2. Words in blue are entries of the encyclopedia: hover one to read it, as in the game.
Vassal Stance is an entry of Crusader Kings III's in-game encyclopedia. The game explains it: "Every Vassal has a Vassal Stance which affects the Opinion they have with you as their Liege, and which Heir they prefer as successor to the Realm." It is part of Vassal. The game also links it as Vassal Stances, Preferred Heir, Unpreferred Heir, Preferred Heirs and 1 more. Patch 1.20.1.2, from game/common/game_concepts/00_game_concepts.txt and game/localization/english/game_concepts_l_english.yml.
Source: game/common/game_concepts/00_game_concepts.txt, game/localization/english/game_concepts_l_english.yml and the English localisation, Crusader Kings III 1.20.1.2.