Translation:We will go on a date tomorrow.
To me it sounds very formal and unnatural. Also for some reason we never tell a person "Let's date" or "we should date"; people kind of hide the date like "Let's go out" or "Do you want to go get some coffee". "We will date tomorrow" sounds like the beginning an arranged marriage.
Same as English "we" - can mean any group of people of which the speaker is one. In fact I'm surprised there isn't a pronoun specifically meaning "you and me" in the admittedly few languages that I know well enough to say. Found this though: https://www.quora.com/Is-there-a-language-which-distinguishes-between-three-types-of-we-1-speaker-and-person-spoken-to-2-speaker-and-others-excluding-person-spoken-to-3-speaker-and-others-including-person-spoken-to