Ok, i had the same problem and i just solved it.
Use "Portuguese" instead "Portuguese-Brazil" in your project, and your Portuguese language of device should work fine.
Here is the problem:
I was trying to set the portuguese language with Portuguese-Brazil at the "+" when i selected the project file, and when i changed my device and my simulator (used both to test) language to portuguese (once there is no portuguese-brazil), the text was coming from the default language (english), what means it was not working.
I tried deleting "Portuguese-Brazil" and adding "Portuguese", and it worked when i changed my devices to portuguese language;
I think that is a bug in XCode, that language "Portuguese-Brazil", since the device has no language like that in Settings > General > International> Language of devices, only "Portuguese"