A mod that allows modification of player data is required.

Example

(https://modrinth.com/mod/modify-player-data)

what is this?

This small data pack adds the ability to save and load custom inventories.

Features

Save and load with a single command

The maximum number of KITs that can be saved is theoretically unlimited

Supports custom KIT names

You can change the target of a KIT by changing the function executor

It also supports off-hand items and armor.

It also supports item's nbt(enchantment,attribute,etc).

How to use?

You can check how to use it by executing "/function wa3kit:howtouse" in the game.

kit save: /function wa3kit:save {id:<kitID>}
kit load: /function wa3kit:load {id:<kitID>}

sorry

This is a personal project, and high-frequency support cannot be guaranteed.