There were only 4 actual signatures on the Treaty of Paris: Adams, Franklin, Jay, and David Hartley (the British negotiator). A fourth American negotiator, Henry Laurens, did not sign.
The Treaty actually did identify the three American signatories as representatives of both the governments of their respective states and of the Continental Congress.
His Britannic Majesty on his part, David Hartley, esqr., member of the Parliament of Great Britain; and the said United States on their part, John Adams, esqr., late a commissioner of the United States of America at the Court of Versailles, late Delegate in Congress from the State of Massachusetts, and chief justice of the said State, and Minister Plenipotentiary of the said United States to their High Mightinesses the States General of the United Netherlands; Benjamin Franklin, esq`re, late Delegate in Congress from the State of Pennsylvania, president of the convention of the said State, and Minister Plenipotentiary from the United States of America at the Court of Versailles; John Jay, esq`re, late President of Congress, and Chief Justice of the State of New York, and Minister Plenipotentiary from the said United States at the Court of Madrid, to be the Plenipotentiaries for the concluding and signing the present definitive treaty
It is also noteworthy that the Treaty itself included corollary obligations from Spain, France, the Netherlands, and several other lesser European powers through a complex system of simultaneously executed documents. It was actually quite a feet to pull it all off as they did.
Well no it didn't. It identified them by former offices. "Late delegate", not "Delegate", "late Minister" not "Minister", etc. All three men represented the United States alone and not any individual state.