Fide rating and Lichess rating correlation

Is there a study or a chart that compares Fide vs Lichess ratings?

I was checking a player's profile, who has a 1634 std Fide rating, he is around 2200 in Blitz in Lichess.

I don't expect a linear correlation between the two. But there must a relation between these two numbers.

There could be a lot of variancy. I for example have a higher bullet than blitz rating which is very unusual. Also not even federated, but beaten a couple NMs.

Classical time control is not very popular online so i believe we can't have some correlation not even with a big margin of error.

lichess.org/forum/general-chess-discussion/fide-vs-lichess-rating
This previous forum post might provides some insights

chessgoals.com/rating-comparison/#Rating_Comparisons

Here, check it out