I have seen Translation Campaigns that requires you to put your previous works/translations. Is there any chance for a beginner, who doesn't have translations yet, to join this kind of campaigns? If yes, how? Thanks!
At first you should create your own portfolio. There aren't many managers that accept unknown translators. You can start making your portfolio by doing some tasks for free.
But if not everyone wants to accept newcomers to complete the translation task, How can you create your portfolio? Is it possible to provide some work that is not located on the bitcointalk resource?