It should be legal in the Lakota nation if Payu is successful with getting acceptance from the tribal elders. It is looking positive. Worldwide I don't think anything is recognized everywhere, and as Borderless marriage is also about equality, some nations are very much opposed to that. (Gay marriage and the like) The motto is "Confirm your love on the Blockchain" -- Initially in most places it will be something in between traditional marriage I would say, but way more of a commitment than just living together. It also depends on if one is a "statist" or not. As I am more a voluntarist, this is just as real as anything approved by the Church or State for me. Legally however, not right away, and certainly not everywhere.