Overall there are a few nice enchantments that will perform well when placed on a crossbow in Minecraft. However, you should always consider placing the multishot enchantment first before others on your crossbow. The reason why is simple, it makes it so your crossbow fire more than one arrow when you use it.
Because of that, there is no reason why you should not have it; it's just so useful for taking out multiple enemies.
It also only consumes one arrow when you use multishot, so you're getting three arrows for the low price of one! After multishot, you should also combine it with the piercing enchantment for deadly effect.
In short, the piercing enchantment will make your crossbow arrows pierce through multiple enemies, so combine that with multishot, and you will become the Minecraft terminator more or less.
Related: Best Minecraft Helmet Enchantments
Now for the last enchantment, you should get is quick charge. Quick charge is a unique crossbow enchantment that lowers the reload times for the crossbow.
Because of this, we highly recommend getting it so you can load and fire the crossbow faster and turn the crossbow into a deadly fast reloading weapon.
Beyond these three enchantments, the following enchantments below are always a nice addition but are by no means the best or required for the crossbow.
Mending is a useful enchantment that will allow you to use orbs of experience to repair your item. Overall, we highly recommend adding it to any tool or item you have, as it it's just really useful, even more so when combined with unbreaking.
Unbreaking is a wondrous enchantment for any item, as it increases durability and will help you keep using whatever item it's on. For that reason, it's always worth considering throwing it on any weapon you plan on using a lot.
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