Terralith adds some blocks to the overworld, which are commonly only found in other dimensions.
I'd like to request some help with adding overworld ore variants:

Blackstone coal ore
Blackstone iron ore
Blackstone redstone ore
Blackstone lapis ore
Blackstone gold ore (not nether gold ore)
Blackstone emerald ore
Blackstone diamond ore
Blackstone copper ore

This would be greatly appreciated, thank you <3

So, for your own end, this should be just as simple as adding the stone type (or whatever it is on the newer versions, it's a bit different) to those stones instead of just nether. In terms of making it work right out of the box, I'll look into it!

Adding "excavated_variants:overworld" to types in blackstone.json results in two identical but separate blocks "Blackstone Quartz Ore" blocks being added to the game. They do not stack with each other.

For some reason this is also the case for "Blackstone Nether Gold Ore"?

Additionally, the world generation seems to not work as intended here; when ores generate in areas of blackstone, the Deepslate ore variants are generated instead of the Blackstone variants (even at surface level, oddly).