Paulenrique, you are a fantastic and reliable resource provider, but I feel "sounds unnatural/awkward in English" is an unsafe claim to make generally, and here in particular. Commenters above have said that it is right in UK English (my dialect) which I believe - and find from my study - that this Portuguese course at least tries to support. It was my instinctive translation, which I would use colloquially and in writing.
Thanks for your advice. I'm not an English native speaker, so what I write here is based on what I have learned through the years... and English has so many variations that I just can't keep them all in my head >.< I'm sorry! And thanks for letting me know it is also right =)
"Whose is the dress" and "Whose dress is it" are subtly different in that the first form would more likely be used when the dress is being pointed out by the person asking the question, whereas the second form makes more sense when the person expected to answer the question has pointed the dress out to the person asking the question.
Does this subtlety correlate at all in Portuguese?