AFL-CIO President George Meany heaped scorn on the Carter administration's conduct of foreign as well as domestic affairs today, but indicated the labor federation may be able to support a modified version of the administration's "real wage insurance" program.

At a press conference after the opening of the AFL-CIO executive council's midwinter meeting here, Meany asserted that the administration's economic policies are failing and suggested sarcastically that it may not even have a foreign policy.

Referring to administration response to events from Iran to Indochina, Meany said: "If something happens, we deplore it, we make a speech or a statement.... Frankly, I don't know what our foreign policy is today."

Relations between Meany and the White House have deteriorated almost to the breaking point in recent months, but his previous criticism has been directed largely at the administration's economic policies. Today he focused on foreign policy and found it equally wanting.

Among other criticism, Meany said the administration acted too quickly in recognizing the new revolutionary government in Iran. As for hostilities in Southeast Asia, he said: "We 'deplore' the invasion of Vietnam by communist China, and we 'deplore' the invasion of Vietnam into communist Cambodia, and we say to the Russians that we would 'deplore' it very much if they got into this thing."

Reminded that he gave President Carter a "C minus" grade at this time last year. Meany said the report card made the president "very, very much upset" and added, "I'm not going to make that mistake again." But, pressed to say if he thought Carter's performance had improved over the past year, he said, "No."

Meany again dodged questions on whether he would support Carter for reelection in 1980. But he virtually ruled out one of Carter's prospective challengers for the Democratic nomination, California Gov. Edmund G. (Jerry) Brown Jr., who has angered unions by advocating a constitutional convention to ban federal budget deficits. The executive council passed a resolution today asserting its strong opposition to such a convention.

Asked about Brown, Meany said: "Oh, yes. He's the fellow who changes so quickly. He's very entertaining, I think."

On "real wage insurance," the administration's proposal for protecting workers who comply with its anti-inflation wage guidelines, Meany and the executive council softened the federation's earlier criticism and indicated there may be grounds for compromise.

In a resolution, the executive council said the proposal, which would give workers who hold their annual wage increases to 7 percent a tax credit of up to $600 a year, should be improved in several ways, largely to guarantee that no low-wage workers or small business employes are exempted.

The council also proposed a tax on business profits that exceed the administration's profit margin guidelines, with revenues from the tax to be used to finance the insurance payments.

"If it [the insurance proposal] makes some sense, if it helps some of these people, especially the low-wage people, and if provisions include an excess profits tax, I suppose we'd give it great consideration," Meany said.

Meany denied this represents a change in position, but aides acknowledged it reflects a "different emphasis," brought about by indications that Congress may consider modifications to make the program more palatable to labor. Said one AFL-CIO official, acknowledging it would mean more money for many workers: "You can't shoot Santa Claus."

The executive council noted that its qualified support for wage insurance does not mean it has dropped its opposition to the administration's anti-inflation guidelines. In answer to a question, Meany said the AFL-CIO is exploring the possibility of a suit challenging the government's plan to deny federal contracts to guidelines violators, but has made no decision.