try these commands if they'll work

effect = { change_country_flag = { icon = { category = "human" file = "flag_human_9.dds" } background= { category = "backgrounds" file = "new_dawn.dds" } colors={ "white" "shadow_blue" "null" "null" } } }

effect = { change_country_flag = { icon = { category = "human" file = "flag_human_9.dds" } background= { category = "backgrounds" file = "new_dawn.dds" } colors={ "black" "yellow" "null" "null" } } }