Moscow — When Leonid Brezhnev sits down with the Communist Party faithful here next week, he is supposed to chart this superpower's policy for the next five years. But all indications are that the 26th congress of the Soviet Communist Party will hurl a lot more chatter than change at a daunting array of economic and political problems.
The congress may, above all, provide a graphic look at the flip side of Mr. Brezhnev's major policy successes in his more than 16 years at the center of Soviet policy.
And more important than any expected policy shift, many analysts here maintain, may be whatever changes are made in the party leadership rolls.
That could afford a further hint of who may run the Soviet Union once Mr. Brezhnev is gone.
An uncommonly frank Soviet political analyst, reflecting a long-held view among foreign Kremlin-watchers, put it this way:
"The current leadership is old. . . . Its chief fault appears to be that it has not created a group of younger men to succeed."
But if any major move to remedy this is in the offing, someone has forgotten to tell the official Soviet news media.
"I think we would have had some public sign by now of major leadership changes," said a Sovietologist in one Western embassy here.
As for major policy turnarounds, the big news may be the lack of big news.
The burly, beetle-browed Mr. Brezhnev, who will open the congress Feb. 23 has given his country years of unprecedented political stability.
But that stability came hand in hand with a stultifying conservatism at home, particularly in attacking an intricately planned economy that often just doesn't work.
Mr. Brezhnev has also built the Soviet Union into a genuine superpower, with unprecedented military might.
But his tanks and warplanes have not snuffed out what his media scorn as rebel "gangs" in Afghanistan. Nor does the Red Army seem to promise a palatable antidote to worker unrest next door in Poland.
President Brezhnev's version of detente has forged unprecedented trade links with the West, particularly with key European states like West Germany. But relations with Europe are strained. Relations with Washington are worse.
Nor are the Soviets on the best of terms with even Communist Parties in Europe. Current indications are that the Italians, Spanish, and French will not be sending their No. 1 men to Moscow.
The congress will have to deal with these issues. More precisely, Mr. Brezhnev will deal with them. Much earlier in Russian Communist history, such party meetings really did debate or, in more recent years, flash hints that such debate was occuring.
In recent years congresses have relayed undiluted policy from the top.Even this function has been eroded under Mr. Brezhnev, whose policy approach leaves significantly less to be relayed.
On the eve of the congress, the consensus among Moscow's tea-leaf readers is that, with some variation from issue to issue, the meeting will produce a traditionally cautious Brezhnev approach to major Soviet problems.
* The economy. The congress may enshrine recent official indications that Soviets may get a dose of the capitalist market economy they're supposed to despise. In Moscow jargon, this means added "incentives" as well as greater emphasis on small private farming plots, rather than lumberingly inefficient collectives.
There will also be, analysts feel, the traditional calls for more efficiency, better and more numerous consumer products, and perhaps a drive to conserve energy.
* Foreign affairs. Mr. Brezhnev is expected to deliver a stern warning to Washington not to "return to the cold war," while not shutting the door altogether on eventually improving relations with the Reagan administration.
He is also expected to stress the mutual advantage of good relations, particularly with West Europe.
On Afghanistan, foreign analysts look for no major change in Soviet policy -- a declared readiness to back talks between the Afghan regime and neighboring states, but only if the new status quo in Kabul is recognized in the process.
Poland may come up only indirectly in the congress's formal proceedings. But there can be little doubt that with East European leaders in town for the conference, there will be at least informal Warsaw Pact talks on a crisis that seems unwilling to go away.