Hehe found the list of codes for adding traits:

I add them by using this command (with general or agent outside city and selected):

give_traits this GoodCommander (insted GoodCommander you can use any of the codes below)

List of Traits for Family Members

GoodCommander 5
GoodAttacker
GoodDefender
GoodRiskyAttacker
GoodAdministrator
GoodInfantryGeneral
GoodAmbusher
GoodSiegeDefender
GoodSiegeAttacker
Intelligent 3
VictorVirtue
PublicFaith
BattleChivalry 5
StrategyChivalry 5
BattleDread
StrategyDread
NaturalMilitarySkill 4
Austere
Energetic
ReligiousActivity
Drink
BloodThirsty
Loyal
HaleAndHearty 3
PoliticsSkill
Rabblerouser
MathematicsSkill
Disciplinarian
RhetoricSkill
StrategicSkill
TacticalSkill
SpyMaster
AssassinMaster
CounterSpy
AssassinCatcher
Upright
Just
InspiringSpeaker
EasternWarlord
Berserker
Girls
Xenophobia
Brave

Princess Traits
GoodPrincess 4
NaturalPrincess 3
PrettyWoman 3

Priest Traits
NaturalPriestSkill 3
StrongFaith 4
GoodDenouncer 5
Righteous 3

GoodMerchant 5
GoodDiplomat 5
GoodAssassin 5
PriestLevel 4 (1 priest, 2 cardinal, 3 elected cardinal, 4 pope)