Currently due to the name mismatch, they are not compatible.

I can sure look into it in the future update. What version and loader are you using?

Forge, and Minecraft 1.19.2

A bit of additional info:
For example the Nether (and End) emerald, diamond, redstone, lapis, coal, silver, iron, tin, and uranium ore are compatible.
The only thing that is not compatible, but is present in both mods is the "Alumin(i)um".

An example of the nether copper ore working with IC2 classic machine:

Been updated for 1.21. Will work on support for 1.20.1.