IMPORTANT:
Make sure you have the _C at the end of the item name/id or it wont work.
Add the below to your game.ini under this line [/script/shootergame.shootergamemode]
you may have to kill your character before seeing cost changes (bug with ConfigOverrideItemCraftingCosts)


the below is the default costs of a Powerful Narcotic

ConfigOverrideItemCraftingCosts=(ItemClassString="TT_PrimalItemConsumable_Narcotic_C",BaseCraftingResourceRequirements=((ResourceItemTypeString="PrimalItemConsumable_Berry_Narcoberry_C",BaseResourceRequirement=10.0,bCraftingRequireExactResourceType=false),(ResourceItemTypeString="PrimalItemConsumable_SpoiledMeat_C",BaseResourceRequirement=2.0,bCraftingRequireExactResourceType=false),(ResourceItemTypeString="PrimalItemConsumable_Berry_Azulberry_C",BaseResourceRequirement=10.0,bCraftingRequireExactResourceType=false)))

Quick break down of the above code (google for a better explanation if needed :P )

ItemClassString="CHANGE TO ITEM YOU WANT TO MAKE"
ResourceItemTypeString="CHANGE TO ITEM YOU NEED TO MAKE"
BaseResourceRequirement=CHANGE TO HOW MUCH ITEM NEEDED
ResourceItemTypeString="CHANGE TO ITEM2 YOU NEED TO MAKE"
BaseResourceRequirement=CHANGE TO HOW MUCH ITEM2 NEEDED
ResourceItemTypeString="CHANGE TO ITEM3 YOU NEED TO MAKE"
BaseResourceRequirement=CHANGE TO HOW MUCH ITEM3 NEEDED