It would be really helpful to be able to make the stone-based blocks in a stonecutter, thanks!

Don't they already?

What version of minecraft and the mod are you using?

Pretty sure that already should be possible. I have recipes for getting stone brick vertical slabs from stonecutting being generated.

I'm running Minecraft 1.18.2 and using version 2.3.0 of the mod.

Indeed, end stones do appear to work, though this doesn't seem to apply to corners and many of the other slabs - I've been checking through JEI, some of the blocks that normally have stonecutter recipes do have them, while others (such as calcite) do not.

Okay will also look into that stuff

Much appreciated, thanks!