It’s interesting that they went with the English names of some countries (i.e. “Supainu”, “Suweden” and “Porando” could have been “Esupaniya”, “Suberige” and “Porusuka” or similar) but chose native ones for some well-known countries like Germany.
of course, how else would non Japanese speaking people read it? Also the country names are on the easier side of pronunciation, so not much is lost when using romanji, it's not like in other SEA languages where tones are lost in Latin spelling