Certainly Hamilton was a classic mercantilist, and Washington signed Hamilton’s proposals into law. (The notable exception was the Report on Manufactures, which Congress rejected.) One might demur that Washington had a different understanding of the president’s role in the legislative process than do today’s chief executives, and so we should not read his signature as signifying endorsement. (See Ketcham, PRESIDENTS ABOVE PARTY.)
Such as Jefferson, Madison, et al., certainly did favor free trade — what Jefferson called “the right to trade freely with all the world.” This was a perfectly anti-mercantilist program, in inspiration and in detail. The best account of the Jeffersonians as heralds of a free trade-based New World Order is Onuf & Onuf, FEDERAL UNION, MODERN WORLD.