eligible_for_fp2_dynasty_legacies_trigger

eligible_for_fp2_dynasty_legacies_trigger = {
	has_fp2_dlc_trigger = yes
	dynasty.dynast = {
		OR = {
			game_rule_unrestricted_dynasty_legacies_trigger = yes
			any_character_struggle = {
				involvement = involved
				is_struggle_type = iberian_struggle
			}
			culture = {
				has_cultural_pillar = heritage_iberian
			}
			capital_province ?= {
				geographical_region = world_europe_west_iberia
			}
		}
	}
}

As written in game/common/scripted_triggers/03_fp2_scripted_triggers.txt.