Game concept
Beneficiary
The game also links it as Beneficiaries.
From the game's encyclopedia
Every participant in a Great Holy War can select a Beneficiary from their Dynasty. Upon victory, the Beneficiary will receive lands in the targeted realm proportional to the War Contribution of their patron ruler.
The largest contributor can force their Beneficiary to receive the main title being fought over.
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.
Beneficiary is an entry of Crusader Kings III's in-game encyclopedia. The game explains it: "Every participant in a Great Holy War can select a Beneficiary from their Dynasty." The game also links it as Beneficiaries. 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.