I think what we need is more weapon versatility to minecraft, much like other games such as terraria! Like the flail, ice sword, or magic staff! But we are not talking about those, we are talking about a completely unique weapon that fits the minecraft theme!

Obtaining

A more interesting way would be some form of a new mob in the soulsand valley. It could either be some kind of scary humanoid creature, or a beast that drops a scythe blade.

This weapon would be about as rare of a drop as a wither skeleton skull, making it a late-game item.

Use

The scythe, when left-clicking, would be similar to the sword. It would also have the sweeping edge ability but would attack slightly faster, and do less damage.

One interesting thing about the scythe is that it wouldn't do any knockback, making it useful for tight situations.

Enchants

This weapon would be compatible with sharpness and sweeping edge (and mending/unbreaking of course). However, it would also have unique enchantments:

Dragging - I-II

Dragging would do the reverse of knockback - it would pull enemies towards you.

Wither's Tip - I-II

This enchantment would apply the wither effect for a few seconds. It would accomplish the same thing as fire aspect on the sword, but be more effective in the nether.

Gleaning/Reaping - I-III

This enchantment would increase the XP dropped from mobs, similar to Looting or Fortune.