In order to use created shop list files, place the "shopList.slt" file in "steamapps\common\Monster Hunter World\nativePC\common\facility"

If the nativePC folder or any necessary subfolders don't exist, create them.

Only the file named shopList.slt will be read by the game, so you can leave the application in "nativePC\common\facility" and create and name multiple files for your own presets, switching them as desired.