Carter administration agreements with South Korea and Taiwan, designed to restrict shoe imports into the United States, were dealt a setback yesterday in a court decision upholding the right of American importers to challenge the voluntary accords.

The U.S. Court of Appeals for the Second Circuit, in New York ruled that federal courts may properly decide if agreements with the two nations were reached properly under provisions of the Trade Act of 1974.

A number of importers charged in a federal suit, that the South Korean and Taiwan shoe agreements were illegal for a number of reasons, including the fact that no public hearings were held.

But government lawyers said the federal courts had no jurisdiction in the matter because trade disputes generally must be heard in U.S. Custons Court.

In Ruling against U.S. Special Trade Representative Robert S.Strauss and a battery of government lawyers, however, the Court of Appeals said there are exceptional cases where the Customs Court would not become involved and where federal courts have jurisdiction.

The shoe case is one of these exceptions, the court ruled, because the administrative's agreements will be enforces by the foreign nations involved and no case would develop for study by the Customs Court.

Under the so-called "orderly marketing agreements" (OMAs) signed with the two nations, South Korea agreed to hold its exports of shoes to the U.S. to 33 million pairs in the 12 months that started June 28 (compared with 44 million in 1976), and Taiwan agreed to limit exports to 122 million pairs (down to 156 million).

At the time, Stephen Lande of the Office of Special Trade Representative said the government did not expect a significant impact on prices or availability of the low-cost shoes these countries ship here.