IN CONVICTING International Harvester's man in Moscow and suspending his five-year sentence, Soviet authorities seem to have walked a narrow line between conflicting political and diplomatic purposes. They fulfilled the domestic imperative of avoiding the full embarrassment of the KGB that acquittal would have produced; the KGB is the police agency that arrested Francis Crawford, evidently in retaliation for the indictment in New Jersey of two Russians for spying. Even so, in the trial the prosecutor and judge repeatedly - surely not by design - showed up the phoniness of the KGB's case.Their crudity established Mr. Crawford's innoncence as effectively as he did by his own defense.

At the same time, the authorities avoided the further jolting damage to Soviet-American relations taht would have resulted from a harsh sentence. The Crawford case is not the only irritant that has cropped up in recent months, but it is a major one and one whose removal has been accorded high priority by those on both sides concerned with larger affairs in both diplomacy and trade.

Since it was entirely at Soviet initative that the Crawford case came about, it has been entirely up to the Kremlin to end it a satisfactory way. In that regard, we note the indication in Moscow yesterday that Mr. Crawford, who wants to depart at once, might not be let out until the New Jersey trial opens Sept. 27. The United States has rightly rejected any thought of a swap of an innocent American businessmen of two espionage suspects. Any delay in Mr. Crawford's departure could only be regarded as a deliberate KGB ploy.

The possibility remains of a swap of the "Woodbridge two" for other persons whose fate has been the subject of concern on the part of U.S. citizens and the U.S. government alike. The convicted Soviet dissident Anatoly Scharansky and the convicted Soviet spy Anatoly Filatov are two whose names have been mentioned in this regard. No matter how common and, yes, useful the practice, there is something forlorn and distasteful about the international trade in human beings. In this instance, it would be necessary to intervence in a judicial process already under way. Nonetheless, if a fair and equal exchange can be arranged, it should be done.