(Sorry I don't speak Portuguese)
Are you talking about settings in the Amethyst app (if yes I don't know how to access them), or settings in the android system?
Discussion
Both. You can stop translations by changing the setting in the app or by adding the language to Android's input language in the phone settings.
Oh, it's only for the auto translation of the messages, not of the UI.
I thought I had missed a setting page somewhere in the app.
Is there a way to re-enable an auto translation?