This are the important files.
itemdb2:
20007,Black_Scarf,Black Scarf,5,20,,100,,0,,0,0xFFFFFFFF,7,2,4096,,60,0,1000,{},{},{} // For costume lower
accname.lua:
[ACCESSORY_IDs.ACCESSORY_Black_Scarf] = "_Black_Scarf",
accessoryid.lua:
ACCESSORY_Black_Scarf = 1000,
I tried this with Feather Beret too. Changed it to Costume ID but it wasn't shown.
What to do?