I've been getting a lot of requests to translate Six Cultures of Play into various languages and for those translations to be posted on various RPG sites, enough that I have been laggardly in responding to all of them. So here's the blanket approval: You can translate Six Cultures of Play into whatever language you'd like and post it wherever you'd like, at no cost to you whatsoever.
All I ask is that you share a link to the original essay somewhere in the post (or video description, or whatever), and that you in turn allow people in whatever language you've translated it to to freely quote from and discuss the translated essay (no licensing or sub-licensing or whatever). I don't care about being credited, but I'd like the original link to be included just so people can check the original text themselves in case they had questions and to help resolve any potential misunderstandings. If you'd like, feel free to post links to where the translations end up in the comments of the original blog post.
Thanks to everyone who has translated it or is interested in translating it for helping to make the essay available more widely to more people who it might help. My intentions are to make things as easy as possible for you and the people you're helping through your translations.