Hi, and thank you for your interest!
ScummVM is being translated using Weblate, a web tool designed to ease translating for both developers and translators.
Translation project for ScummVM into Portuguese (Portugal) currently contains 960 strings for translation and is 18.7% complete.
If you would like to contribute to translation of ScummVM, you need to register on this server.
Once you have activated your account just proceed to the translation section.