One could assume that if he is considering retiring to Brazil he is aware that they speak Portuguese.
I suggest contacting
A taxa de homologação não será mais cobrada. - LABRE the amateur radio organization of Brazil. They can undoubtedly answer your questions.
The present political climate in Brazil is volatile. There are certain parts of Rio where walking around with a radio would be foolish even if legal.
I spent some time in Brazil (also Argentina and Uruguay) in 2016. I saw lots of evidence of amateur radio activity. I did not attempt to obtain a reciprocal license due to not speaking Spanish or Portuguese.