ftf I'm not certain if I misunderstood the description, but one thing for sure is that it's sneak right clicking on the anvil that will consume gold ingots but not sneak lieft clicking.

I successfully stuffed some ingots into a pickaxe and the counter appeared on the tooltips, but mining coal, diamond and emerald ores with it leads to nothing special, 1 drop per ore, nothing got doubled.

Maybe I misunderstood the word oreGem in the description but it seems like an Ore Dictionary and afaik in 1.16.5 we use Tags instead of OreDicts.

In 1.16 the version is bugged out.
We kinda went through all enchantments with a Mod Breaker Tester (Yes he broke every single mod of mine even so i thought they were 100% stable) and we found roughly 15-16 enchantments being broken.

1.12 got the fixes already but then life came away and the other two versions had to be delayed... Yes should be addressed next weekend hopefully.

TL:DR: We know, we had a giant testing spree, we already planed a patch, 1.12 managed to get done but then I ran out of time...
ETA is next weekend.

yeah this is now fixed.