BackSlot

This mod adds two slots to your inventory, the backslot and the beltslot, mainly for weapons.

Press "G" to put your trident on your back and "Shift + G" to add your sword to the belt

Backslot: Swords, Tools, Trident, Ranged Weapon, Fishing Rod

Beltslot: Swords, Tools, Flint and Steel, Shears

If the hotkeys change after each restart, install amecs

Addon:

Instead of having one sword on the belt and the other one on the back you can have both on the back with BackSlotAddon

This mod is developed for Fabric.

There are no plans to develop a Forge version. 

Modpack Permission:

Feel free to use it in any modpacks

Bug Report:

Just report bugs at the github page