I think it would be helpful for modpack makers to have the ability to add custom enchanting stats to blocks, either via datapacks (in the form of recipe jsons) or via a craftweaker api. I'd like to use this feature to add custom Eterna, Quanta, and Arcana values to existing blocks from other mods. (If it's exposed as a public API, it could also be useful for other modders wanting to add integration.)

That exists, it's just only supported in 1.15 for the time being. Development will be resumed on 1.16 after forge is stable. The format is here: https://github.com/Shadows-of-Fire/Apotheosis/tree/1.15/src/main/resources/data/apotheosis/enchanting_stats

oh, thanks! I'm actually making a pack in 1.15 so this is perfect :) I guess it hadn't occurred to me to check an older version of the source. ;P Thanks a bunch!