So far Liferea actually has localized feedlists for English, Brazilian Portuguese, Bulgarian, Catalan, German, Spanish, Basque, French, Dutch, Polish, Russian, Slovakian, Slovenian and Turkish. So if your language is missing in the list, make one and submit it upstream! Or attach it to the bug report and I’ll forward it. You can base it in any of these. Hint: make them as distro neutral as possible, since they are targeted upstream! Also note that with the current implementation, there needs to be a Translation for your language in order for the localized feedlist to be used, since it’s set up in one string translation.
It’s time to make Liferea rock in Ubuntu a lot more, helping Liferea upstream providing localized feedlists too!