Which real-world rating: US, Europe, Japan, China, Korea, New Zealand, …? Each of them is on a different scale. Even online ranks aren’t in sync. But the answer to this question is probably no in any case.
OGS rank difference between two players is 1 if a game with handicap 1 gives both players a chance of 50% to win the game (assuming the weaker player plays as black).
OGS doesn’t have such a feature. You can find a one-time snapshot of the top rated players is the forum: Top OGS players (more serious this time)
You can read the discussion the if you are interested in why such rankings do not work.