They mean sparkling wine. It’s called Perlwein in German, hence the mistranslation.

Can the term potency also be used to refer to the exponent in English? Because that is what is meant by the terms in the other languages and I haven’t come across that usage of the word potency in English

That sounds like unnecessary effort when there is a perfectly serviceable audiobook version to listen to!

What’s the difference? (Asking as a non-native English speaker)