The empresario system started way before Mexico was independent, so the answer will depend on whether you consider empresarios appointed by Spain as counting or not. If so then, Philip Alston, in 1790, was appointed an empresario in New Madrid (Missouri) and before him George Morgan was appointed empresario there by Spain.
European Americans renamed the settlement New Madrid in about 1780 under the auspices of Spanish Governor Bernardo de Gálvez, who was appointed to rule Spanish Louisiana (the land west of the Mississippi River), and Manuel Pérez, Lieutenant Governor of Upper Louisiana in Saint Louis. They welcomed settlers from the United States, but required them to become subjects of the Spanish crown. In addition, they had to agree to live under the guidance of his appointed empresario, Colonel George Morgan, an American Revolutionary War veteran from New Jersey. Morgan recruited a number of American families to settle at New Madrid, attracting a few hundred people to the region. link