The only ones that are not translations or reskins that I know are
Duke 3D (Gen) - very interesting and surprisingly playable but not really a good game also crazy hard
Woody Woodpecker (Gen, SMS) - it sucks
Street Fighter 2 (SMS) - it sucks
Show do Milhao 1 and 2 (Gen) - it's a trivia show like Who Wants to be a Millionaire, very fun if you can understand portuguese but it's only a slideshow of questions and answers
Nightmare Circus - cancelled norwegian game that was only released over the Sega Channel in EU and NA, but got a full cartridge release in Brazil. It sucks
I'm writing from memory but there might be others. Also I don't know if there are japanese games translated or published in Brazil that were unreleased in Europe or Japan. If I recall correctly International Superstar Soccer 2000 and F1 Racing Championship for N64 in NTSC are exclusive to Brazil.