Why make a model of Lysithea if there are some already?

Because the others I found have been trained with images of the character in its academy version and its war phase version, which causes that when one wants to make one of the two sometimes came out with mixed details of the other version (purple uniform instead of black for example).

Personally, when a character has several hairstyles or changes her look a lot, I prefer a lora for each one. That's why I made one of the small version of Lysithea (and because I like this one better).

It is very likely that the uniform will come out even if it is not described, so put (uniform, garreg mach monastery uniform) in negative prompt if you don't want it.