Compatibility / Prefixs

ItemsAdder

This plugin is compatible with ItemsAdder, to use this compatibility in the "material" section you will have to use ia:namespace:item_id

Oraxen

This plugin is compatible with Oraxen, to use this compatibility in the "material" section you will have to use or:item_id

StorageMechanics

This plugin has its own items too, to use them use the sm:item_id prefix.

Minecraft Items

To use vanilla Minecraft items use the mc:item_id prefix
You can use nbt also mc:{id:"minecraft:stone",Count:1b,tag:{Enchantments:[{id:"minecraft:efficiency",lvl:1s}]}}
Another Example
mc:{id:"minecraft:player_head",Count:1b,tag:{SkullOwner:{Id:"add2598d-0101-44d6-ad63-6b8b96dcee51",Properties:{textures:[{Value:"eyJ0ZXh0dXJlcyI6eyJTS0lOIjp7InVybCI6Imh0dHA6Ly90ZXh0dXJlcy5taW5lY3JhZnQubmV0L3RleHR1cmUvODM1MWU1MDU5ODk4MzhlMjcyODdlN2FmYmM3Zjk3ZTc5NmNhYjVmMzU5OGE3NjE2MGMxMzFjOTQwZDBjNSJ9fX0="}]}}}}

MMOItems

This plugin is compatible with MMoItems, to use this compatibility in the "material" section you will have to use mmoitems:type:id(:level:tier) the (Level:Tier) is optional, but if you place one of the two, you need to place both.

MythicMobs

This plugin is compatible with MythicMobs, to use this compatibility in the "material" section you will have to use mythic:item_id

MythicCrucible

This plugin is compatible with MythicCrucible, to use this compatibility in the "material" section you will have to use mythiccrucible:item_id

CustomItems

This plugin is compatible with CustomItems, to use this compatibility in the "material" section you will have to use cui:item_id

Executable blocks

This plugin is compatible with Executable blocks, to use this compatibility in the "material" section you will have to use eb:item_id

Executable Items

This plugin is compatible with Executable Items, to use this compatibility in the "material" section you will have to use ei:item_id

Soft Depend:

PlaceHolderAPI
ItemsAdder
Oraxen
WorldGuard
MythicMobs
MMOItems
CustomItems
ExecutableItems
ExecutableBlocks
MythicCrucible