CustomRarity

Allows pack makers to define Item Rarity by either NBT or config file. Requires ClothConfig and has optional ModMenu integration.
Best for use with mods like Legendary Tooltips and Immersive UI.

Examples

Define by NBT:

/give @p stick{CustomRarity:"Epic"}

This mod also comes with Item Modifiers:
/item modify entity @p container.0 customrarity:rare
will modify the item in the first slot of your hotbar. Item Modifiers can be used in loot tables.

Define by config:

    "uncommons": [
        "minecraft:diamond"
    ],

NBT has precedence over config, and config has precedence over vanilla rarity value.