Perfect!

Could you please provide your name and email address?

Thank you for your interest to contribute. 👍

The easiest way to edit the translation files is probably by using the Qt tool Linguist. The "goal" would be to have all translations with a green tick in its GUI.
Currently, there are quite a few string that don't have an (updated) translation for Brazilian Portuguese. Usually, it is just a few new strings for each new major version.

If you are interested in becoming the new translator for Brazilian Portuguese, we'd like to add your name and email address to the list of translators: https://github.com/gnu-octave/octave/blob/default/libgui/languages/translators

Translators on that list would get an email invitation to update the translation files once they are updated for a new major version of Octave. That is usually once a year (often close to the end of the year).

Would that be ok for you?

Which operating system do you have? (In case, you'd like to get help installing Qt Linguist.)

What would be the main idea?

Just to look at the pt_BR.ts file and look for missing translations and/or checking if somethings is wrong or misspelled?

Hello,

in file

libgui/languages/pt_BR.ts

line 1324 reads as

<translation type="unfinished">O arquivo &apos;%1&apos; paree ter sido modificado por outra aplicação. Deseja recarregá-lo?</translation>

The word "paree" is incorrect, it should be "parece", so, line 1324 should read as

<translation type="unfinished">O arquivo &apos;%1&apos; parece ter sido modificado por outra aplicação. Deseja recarregá-lo?</translation>

Kind regards,
Leonardo