[cpach]

I can see why it would be hard to find one set of words that are easy to pronounce/understand in every language and every culture. But perhaps that isn’t necessary? I’m thinking that this feature needn’t be available in every localized version of GnuPG. Or that there could be localized word lists for various languages.

[e12e]

Maybe. I think sticking to something like the phonetic alphabet or "simple English" would be ok.