Both google translate and deepl.com translate both the English “soup of the day”, the French “soup du jour” and German “Tagessuppe” as “dagens soppa” which is the “not night” day. So it still implies a nattens soppa.
I would argue that in French “soup du jour” is the correct meaning, as in “today’s soup”. And it would otherwise be “soup de jour” as in “day soup”, which doesn’t exist.
Asking the real questions
Both google translate and deepl.com translate both the English “soup of the day”, the French “soup du jour” and German “Tagessuppe” as “dagens soppa” which is the “not night” day. So it still implies a nattens soppa.
I would argue that in French “soup du jour” is the correct meaning, as in “today’s soup”. And it would otherwise be “soup de jour” as in “day soup”, which doesn’t exist.
I would argue that the French uses the article more often than English does so it is correct to omit it when translating
Mmm night soup. Somehow I feel like night soup should be sexual, but I have no idea how or why.