Members of the League of Themselves don't have to actually appear in a TV show to add credits to their body of work in Toobworld. All that is needed is for a TV character to mention something that they did, prefereably something fictional.
For example, we actually saw Tom Hanks getting his pants zipper worked over by a waitress in a four star restaurant, thanks to 'The Naked Truth'. So that established the televersion of the two-time Academy Award winner in Toobworld. But thanks to 'Unhappily Ever After', we know he also clobbered the main character with his Oscar.
We didn't see it happen, but we were told it did, and that's good enough.
So with that in mind, we can now use the League of Themselves to link 'Studio 60' to 'The Sopranos', thanks to the legendary Lauren Bacall.
In his disturbing pursuit of his boss Jordan McDeare, Danny Tripp flooded her office with letters of recommendation from noted celebrities in all walks of life. (When she begged him to stop, - to stop the entire courtship idea, - he could have done the noble thing and accepted that she was not interested. Instead, he told her no. TV critic Alan Sepinwall had a word for his behavior: "squicky".)
One of the letters of recommendation was from Ms. Bacall, who last year was mugged for her celebrity gift basket by mobster Christophuh Moltisanti in an episode of 'The Sopranos'.
So Ms. Bacall is the link between 'Studio 60' and 'The Sopranos'.
Technically, Martin Scorcese also links the two series. He also sent a letter of recommendation to Jordan on Danny's behalf, and he was also seen in 'The Sopranos'. However, he was portrayed by a lookalike and so didn't actually appear as himself.
But the lookalike was seen so fleetingly and was so convincing in the look, that I'm willing accept him as the real thing.
The film director did portray himself in another HBO series, 'Curb Your Enthusiasm', in which he directed Larry David in the role of a mob boss.
I guess those scenes can only be seen in the Toobworld version of "The Departed".....