What are the names of any of Shakespeare's unpublished plays?

There are two supoosedly "lost" Shakespearean plays: "Love's Labour's Won" and "Cardenio." There's a great deal of controversy about whether these plays are truly lost plays; many believe they exist, just under a different name. There are likely to be more than just these two. Half the plays that appeared in the First Folio had never been printed before, and it's unlikely the compilers could collect all the plays.

"The Two Noble Kinsmen", which Shakespeare is credited with co-writing with John Fletcher. who took over as dramatist of The King's Men after Shakespeare, was published in 1634.

https://en.wikipedia.org/wiki/The_Two_Noble_Kinsmen

No one actually knows who wrote "Arden of Faversham", which was published in 1592.

https://en.wikipedia.org/wiki/Arden_of_Faversham

"A Yorkshire Tragedy" was published in 1608 as the work of Shakespeare, but the modern consensus is that it was written by Thomas Middleton.

https://en.wikipedia.org/wiki/A_Yorkshire_Tragedy

The latter two of these works are considered to be part of the "Shakespeare Apocrypha" -- works sometimes attributed to Shakespeare but not believed to be written by him.

https://en.wikipedia.org/wiki/Shakespeare_Apocrypha

But the only two plays generally attributed to Shakespeare and "lost" are, as noted above, "Love's Labour Won" and "Carenio" (which, like "The Two Noble Kinsmen", was a Shakespeare-Fletcher co-composition).

https://en.wikipedia.org/wiki/Shakespeare_Apocrypha#Lost_plays

"Love's Labour Won" may actually exist under another title, because Shakespeare was known to update plays and change titles. But the question of "Cardenio" (based on a story in "Don Quixote") has fascinated people since the 1600s, as discussed in the Wiki article.

https://en.wikipedia.org/wiki/Cardenio