Hey, thanks for pointing this out. I can’t remember if it is just wrong, or I moved it. I have fiexd up the FAQ now.
You can find that field in dashboard > SpeakOut! > settings > petition form tab
Unfortunately for you, the plugin is linked to the WordPress language. It can’t be done at the moment, but I just had an idea on how it might be that I will explore.
Meanwhile, the closest you can get is to display the petition message as text on different pages. e.g. one page is English and has the message text in English above or below the petition, another page has the message text in German. However, the petition form itself will be in the site language. There may be a plugin that will do this, but I am not sure if it will work.