We all know you can play against cosumi in blindfold mode. But you can see the board there and the last move is shown on it.
It doesn’t resemble real blindfold experience. If you ever saw people play blindfold, moves are called out by voice and often the players do have a real blindfold on. So they don’t have an empty board in front of them with the moves shown on it.
Voice call-out over the internet is a bit difficult with pronunciation difficulties etc. But we can come close to it by pming each other our moves.
So that’s what we with @Satomi did. We also flooded the chat with garbage so only the last move is visible and we aren’t allowed to scroll back. And no board use allowed. Only your head.
This is much tougher than cosumi. I’m not sure if I recommend trying it. It borders that line where it’s not fun anymore but torturous. I guess you could try it one time to see if you like it.
You can look over the game record with my commentary: