Of course, you are allowed to translate it and we would be very happy to have our topic on Bitcointalk's Portuguese local board. 
If a translation, even of one of my posts, is managed by GazetaBitcoin here, it's enough to have approval by GazetaBitcoin.
When you are ready, you can announce it in our original topic.

I almost forgot about this post made by 1miau. First of all, thank you for these words, dear 1miau! I am more than flattered to know you reply on me here.
So having this in mind, I believe that cygan's suggestion is feasible, as we also have 1miau's approval for translating the topic Important to know: Difference Coin / Token and shady marketing practices.
Since nobody objected to this proposal, I believe we can add it to OP...

3. gagux123 said he is working on the last needed translation for first topic, thus we'd only need his confirmation that he is actually doing it, thus nobody should spend efforts for doing it as well.