To change outfits in Fatal Frame: Maiden of Black Water, you must first play through both the tutorial and first mission. After the first mission, players will choose to change outfits by pressing Y on their control when at the load menu.
You can also see what the controls are for you by looking at the bottom of the screen shown below. Pressing the costume button will take players to another screen with a vast list of options for each character you can play as in Fatal Frame.
To change characters in this menu, use the arrow keys on your controller. When you find a character you want to change an outfit for, use the arrow keys again and go down the list until you find something you like.
If you find an outfit, you will need to press the A key to purchase the outfit with points you earn by taking pictures of ghosts and other items.
Each outfit will also cost something like 10k points, while accessories will cost a little fewer points. You can also find pre-order items in this list if you bought the game early. However, the items are only equipable for certain characters.
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