Translation:We don't need a visa for this place.
I believe "we don't need visas for this place" should be an acceptable translation due to the ambiguous nature of the plural in Chinese. Since the subject is plural I believe the Chinese phrase can map to both "We don't need a visa" (as in each person in the group doesn't need a/one visa) "We don't need visas" (as in we don't need to get the visas we as a group would have needed)
Well 這個地方 means "here." 這個地方 and 這裡 basically means the same thing in Chinese. Btw, I'm using traditional Chinese so the characters may seem different from what this app uses.
That's right. For reasons best known to itself Duolingo seems to favour a more literal translation here.
But "这个地方" = "this place" and while it might be a slight paraphrase, in this sentence I think you can say "this place" = "here".
According to my daily life as a native speaker, I can hardly recall any situation where they can't replace each other. That said, I'm Taiwanese and how we speak Chinese may be different from people from China (which is what Duolingo is teaching), so there might be many examples where they have slightly different meanings that I'm not familiar with. But speaking of this sentence specifically, I believe they are the same.
Hopefully someday everybody in the world say this sentece for every country.