UNITED NATIONS, N.Y.--Soviet Foreign Minister Eduard A. Shevardnadze accused President Reagan yesterday of harboring "evil designs" for a first strike with the Star Wars system, but he said a "realistic possibility" still existed for a superpower sumit.

In an address to the 41st General Assembly, Shevardnadze called President Reagan's U.N. address of Monday "regrettable" and "propagandistic."

He mixed conciliation with an attack on U.S. strategic arms policies.

"Whatever is done to conceal it, the so-called defensive space shield is being developed for a first strike," Shevardnadze charged.

"Evil designs are being passed for good intentions, and a sword for a shield." he said.

Before his speech, the Soviet foreign minister had an unscheduled 45-minute meeting with Secretary of State George P. Shultz, apparently to discuss the confinement of American reporter Nicholas S. Daniloff '56 in Moscow on spy charges.

Neither side issued a statement afterward.

Shevardnadze did not mention Daniloff in his speech, but the Soviets have been saying without elaboration that Daniloff, Moscow correspondent for U.S. News & World Report magazine, could be freed "very rapidly" if the U.S. administration took the right course.

Shevardnadze addressed the General Assembly on the second day of its so-called "general debate," an annual event which gives heads of state and government, foreign ministers and other officials of the 159-member world body a chance to deliver policy statements for their governments. Yesterday's speakers included British Foreign Secretary Sir Geoffrey Howe and Japanese Foreign Minister Tadashi Kuranari. Both expressed the hope for another superpower summit this year.

Striking a conciliatory note, Shevardnadze said in his address:

"Lately, encouraging outlines of meaningful agreements have been emerging. A summit meeting is also a realistic possibility. We could move forward rather smoothly, if that is what the U.S. side wants."

Shevardnadze urged Washington to follow up its words about reducing the threat of nuclear war "with practical deeds."

"I am authorized to state that the Soviet Union is prepared to sign at any time and in any place a treaty on a total prohibition of nuclear weapons tests," he said.

Shultz sat grim-faced through Shevardnadze's speech. He later told reporters he welcomed the Soviet proposal for eliminating nuclear weapons, "something President Reagan has long advocated."

Even more welcome, Shultz said, would be "practical steps" by the Soviets at Geneva arms talks to "join us in the radical reductions we've proposed there."

In his 37-minute speech Monday, Reagan mentioned his original proposal for a mutual 50 percent cutback in strategic bombers, submarines and missiles.