I don't have any information to add, but I do wonder if they kept Barbie's blonde hair and blue eyes for this--or any other cultural--doll. If the goal was simply to learn about the clothing from different places, perhaps this was a good idea; if they aspired to do more, it seems unlikely they achieved the goal.
I believe the Barbie Carnival Series (Rio de Janeiro Barbie) was introduced in 2006. It was part of Barbie's/Mattel's "Dolls of the World" series, and it was based on a Brazilian-styled carnival costume. According to reviewers, the costume has a quite authentic look. The skimpy costume was considered somewhat risque, although it certainly wasn't much more revealing than previous bathing suit Barbies.