Are you annoyed with how long it takes to oxidize your copper? Well this is the datapack for you!

This datapack allows you to smelt copper blocks in a furnace or blast furnace to further oxidize them by one stage. For example, smelting a copper block will yield an exposed copper block, smelting an exposed copper block will yield a weathered copper block, and so on. This works for all unwaxed variants and styles as of 1.21. This pack is not backwards compatible to previous versions.

It's not particularly realistic, but smelting allows you to speed up the oxidation process while still keeping it from being instantaneous like a crafting recipe would do, making for a nice balance, since this still takes time. You also don't get any xp from smelting copper to oxidize it.

Hopefully this is useful to you!