I found this matter on a site well know in brazil, read to report below carefully.
According Chaverot Bertrand, director of ubisoft in Brazil, this desire for us Brazilians may be closer than we thought. Chaverot revealed that the company already makes a research on an episode franchise set in Brazil.
The development team already has several ideas on how to build a scenario based on a particular moment in the history of Brazil and that fits perfectly in the millenial plot between Templars and Assassins, but so for nothing is decided. Said Bertrand However, there is as yet say wether it will be in Assassin's Creed 4 or future titles in the series.
Particulary as own review, I was very happy with this news because until I'm Brazilian, I ask you to forgive me if my translation is not good, my english is bad :)