Could GOG team translate for portuguese [BR]...

P l e a s e ???

I think you're asking the wrong people. GOG aren't the developers, they're just publishing it on their site. I guess it's Beamdog you should be asking. Personally, I don't see it as likely. The game has a lot of text, so it's not exactly a trivial thing to do.

You should ask here if a portuguese fan-made translation exists: https://forums.beamdog.com/categories/portugu%C3%AAs.
Good luck!