In the translation and the tools forums, there's a couple posts that tell you how to translate RPG Maker and QSP games and some of our members also know how to do that. Not only that, they know of resources like TFGamessite and ULMF. For Ren'Py, you can use Sams' unren and notepad++ to get that done for the ren'py games. For HTML or twine?? Again, notepad is a good fit for that.
My only thing I don't know of is a working tool that will rip the text, translate or let you translate it, and then put the translated text back into it. That's usually involving 2 or more programs and NUMEROUS steps.