In this guide, you will learn how to find The Samurai Set in Monster Hunter World. It is just a costume and it will not affect your armor.
First, you need to go to your house and speak with the housekeeper, as shown in the image below. After speaking with him, you need to claim your DLC and also claim the add-on bonuses.
After doing that, you will find a red chest in your house. When you get near the chest, you have to click on the Change Appearance and then navigate to Layered Armor Settings located at the bottom.
After that, you will have to equip your samurai set, and you can customize the color of the scute as well. It is a cosmetic item, so that it won’t affect your armor.