The attributes of an item are inherent, including fixed and variable attributes. For example, if an item has durability, it needs to add both fixed and variable attributes of durability

Fixed attributes (UItemAttribute_Stats): Used to store some fixed attribute data, such as maximum durability, materials required for production, mesh volume, etc
Variable attributes(UItemMutableAttribute):Store variable data, such as current durability, current ammunition remaining quantity, and current reinforcement information
Fixed attributes do not require network replication, variable attributes will participate in network replication, and serialization has been implemented

All attributes can be inherited and modified in the blueprint
Variable attributes require the implementation of a Replication function, which is used to copy attributes from an attribute (in ItemBuildInfo) to the corresponding item variable attribute. Only the variable of Other needs to be written to the corresponding variable
Example(C++):
virtual void Replication_Implementation(UItemMutableAttribute* Other) override {

UItemMutableAttribute_Durability* OtherAttribute = Cast<UItemMutableAttribute_Durability>(Other);

Durability = OtherAttribute->Durability;

bIsBreak = OtherAttribute->bIsBreak;

}

Variable attribute:

UItemMutableAttribute	Variable attribute
Replication	Copy function, which implements the function of copying variable attributes of the corresponding item from BuildInfo
UItemMutableAttribute_Durability	DurabilityVariable attribute
Durability	Current Durability
bIsBreak	Is Item Breaked
UItemMutableAttribute_LauncherWeapon	Launcher Variable attribute,For example, bows, guns, etc
AmmoClass	Ammunition item foundation (ammunition type)
ClipAmmo	Remaining ammunition, the remaining ammunition of this weapon (ammunition in the magazine), does not count as items in inventory
UItemMutableAttribute_Enhance	Enhance Variable attribute
StarRating	Current star rating
StatPoints	An array of enhancement points, where the enhancement bonus values are stored
ExtraStatPoints	Special enhancement point array, storing non player attribute enhancements, such as item durability enhancement

Fixed attribute:

UItemAttribute	Fixed attribute
AttributeType	Attribute Type,EItemAttributeType
MutableAttribute	Variable attribute create
UItemAttribute_Enhance	Enhance Fixed attribute
bManualEnhance	Allow active reinforcement, such as items that require players to use materials on the reinforcement platform for reinforcement, not the system
MaxStarRating	Maximum Enhancement, Star Rating
EnhanceTable	Strengthening platforms, such as workstations, strengthening platforms
EnhanceResource	Materials required for strengthening (basic)
EnhanceResourcePow	Reinforcement Material Usage Index Algorithm: Resource=Default+Default * StarRating ^ EnhanceResourcePow), adjust the amount of strengthening materials based on star rating, and fill in 1. f if no material is added step by step
EnhancementSuccessProbability	Enhance the probability of success and consume materials in case of failure
EnhancementFailureBreakProbability	The probability of destruction after reinforcement failure, 0 to 1, where 0 is not destroyed
bRemoveAfterBreak	If the enhancement fails and it is destroyed, it will be directly removed. If false, the durability will return to 0, and if true, the item will disappear
bAllowAppointEnhanceStat	Allow players to specify attributes for reinforcement, for example, players only enhance the attack power of weapons, fill in true if random reinforcement is not performed, or enable this function to specify attribute ID -1 for random reinforcement
EnhanceStats	Strengthen the basic attribute array (one item at a time)
EnhanceExtraStats	Special strengthening of basic attributes, such as durability
Enhanced explanation	Randomly generate a reinforcement rate based on the maximum and minimum reinforcement rates for each item in the reinforcement attribute list and add it to the reinforcement variable attribute list Enhanced attribute algorithm: *Original attribute value Basic attribute multiplier * Enhancement multiplier Balance adjustment can adjust the original attribute value and the base attribute multiplier, The original attribute value affects the attributes of unreinforced and reinforced items The basic attribute multiplier** only affects the strengthened item attributes
FItemEnhance/FItemExtraEnhance(Struct)
StatType	Attribute Type
BaseMultiply	Basic attribute multiplier
ProbabilityWeight	Probability weight, used for random reinforcement
MinEnhanceMultiply	Minimum reinforcement rate
MaxEnhanceMultiply	Maximum reinforcement rate
UItemAttribute_Equip	Fixed attributes of equipment, including equipment bar and shortcut bar
EquipSlotType	Equipment slot type
ItemActorClass	Item sub entity type, used to generate weapons and other entities, clothing and other appearances are not set here
UItemAttribute_RequiredLimit	Restricting fixed attributes, used to restrict players from wearing level equipment, etc
MinLevel	Minimum level
UItemAttribute_Stats	Fixed equipment value attribute
Stats	Attribute array
bApplyStatsWhenEquip	Apply it to the status component when equipping, for example, adding attributes when equipping clothes to the equipment bar, removing and subtracting attributes, and doing nothing on the shortcut bar
UItemAttribute_Durablity	Durable fixed attribute
MaxDurability	Maximum durability
bCanDecay	Can it decay? After a certain period of time, the item will decay and cannot be used or removed
DecaySecond	Decay time, in seconds, will only spoil one item at a time. The durability of the remaining items after decay will be reset
DecayGiveItem	Give items after decay, such as giving players rotten meat items after meat decay
bDisableRemoveAfterDecay	Whether to remove items after decay, such as weapons with decay time, which can be repaired after decay, but using this function will not be able to provide them during decay DecayGiveItem
UItemAttribute_StaticMesh	Static mesh fixed attribute
StaticMeshs	Static mesh array, used to add static meshs to items, such as weapons
UItemAttribute_SkeletalMesh	Bone Mesh Fixed Attributes
SkeletalMeshs	Bone mesh, used to add bone mesh to items, such as armor
UItemAttribute_Use	Use fixed attributes, such as meat being edible
UseType	Usage type Self implementation in Delegate delegation GiveBuff ModifyStatus increases attribute values, such as restoring health after using a blood bottle or increasing hunger through food. This mode is for fast recovery and requires an increase in the use of CDs. If slow recovery is required, please use GiveBuff mode
UseColdDown	Use cooling time
ColdDownGroup	Cooling grouping, such as using the same cooling CD for large and small blood bottles, setting this item to the same name is sufficient
ModifyStats	Add a list of attribute values for use in ModifyStatus mode
GiveBuff	Add BUFF and use it in GiveBuff mode
UseMode	Usage mode for playing sound effects and animations, Need to delegate inventory component ->OnItemUseNotify
UItemAttribute_Craft	Craft fixed attribute
Resource	Materials required for production once
GiveQuantity	How many items to give at once
ExtraItem	Craft one and give extra items
CraftTable	Craft platform, such as workbench, machine tool
CraftTime	Time required for Craft
CraftGroup	Craft groups for UI grouping
bCanRepair	Can it be repaired? The materials used for repair will vary based on the current durability, and the minimum cost for one repair is 1 material per sample
RepairConsumptionPercentage	The material multiplier required for repair, default to 0.5, only half of the material needed to repair a damaged item at once
bUseCustomRepairResource	Use custom materials to repair items. If you use this option, the RepairConsumptionPercentage will not be used, and the current durability will not be calculated. For example, one sharpening stone will be consumed each time you repair a weapon
CustomRepairResource	Custom repair materials
UItemAttribute_Weapon	Weapon Fixed Attribute
bUseAmmunition	Equipped with a magazine that can store bullets
AvailableAmmunition	Permissible types of weapons and ammunition
UItemAttribute_Projectile	Fixed attributes of missiles, such as arrow items
ProjectileClass	Type of missile,APrimalProjectile