Game concept
Scales of Power
The game also links it as Scales.
From the game's encyclopedia
During Power Sharing, the balance of power between the Liege and their Diarch is measured on the Scales of Power.
As the Scales tip towards the Diarch, they unlock Borrowed Powers and may add costs to the Liege's Mundane Actions.
As they tip towards the Liege, it instead makes it easier for the Liege to end the Power Sharing.
The Scales can be swung by:
• Using the Swing the Scales of Power Character Interaction against the opposing party
• As the Diarch, serving your Liege well (however cynically) in Mandate events
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.
Scales of Power is an entry of Crusader Kings III's in-game encyclopedia. The game explains it: "During Power Sharing, the balance of power between the Liege and their Diarch is measured on the Scales of Power." It is part of Power Sharing. The game also links it as Scales. Patch 1.20.1.2, from game/common/game_concepts/04_ep2_game_concepts.txt and game/localization/english/game_concepts_l_english.yml.
Source: game/common/game_concepts/04_ep2_game_concepts.txt, game/localization/english/game_concepts_l_english.yml and the English localisation, Crusader Kings III 1.20.1.2.