for most (3/4 models not need anything(but works if you want change, for 1/5 you need add hairstyle, and for few better to write hair color and some accessories, like hairband(or you get only half of images in default outfit)))

(i train specially for you don't need write this things as default behaviour, because if you use multiple character loras for multichar images it easier to control this way (styles/colors don't leaks, and prompt shorter))