Coach Joe Gibbs said yesterday the Washington Redskins, who do not have a first-round choice, still could wind up with as many as four rookies capable of starting if the National Football League draft develops as he hopes today and Wednesday.

General Manager Bobby Beathard, who spent most of yesterday on the telephone discussing trades, also may be able to swap cornerback Lemar Parrish for a middle-round pick before the draft ends. Beathard said at least two American Football Conference teams showed interest in Parrish, who has asked to be traded because of a conflict with Richie Petitbon, the defensive coordinator.

"We are very well prepared and I feel very good about this draft," said Gibbs. "Our draft board probably will look radically different from a lot of other clubs'. That's because we have a lot of guys who we really like that aren't as highly regarded by other teams. We have a feel for them and we are convinced they are good."

The Redskins' first selection will be the 49th in the draft. They also do not have choices in the fifth and eighth rounds.

They have four major needs: a pass-rushing defensive lineman, an aggressive cornerback, a fast wide receiver and a pass-catching tight end. It is likely that first pick, in the second round, will be used on either a wide receiver or a cornerback unless a defensive lineman the Redskins regard highly still is available.

Gibbs and Beathard would like to add much-needed quickness to the defense. But neither would rule out using that No. 2 to take a running back or an offensive lineman.

"I wouldn't want to take anyone in those two positions or at linebacker unless they have a chance to be a star," said Gibbs, who concentrated on scouting tight ends the last few months.

"We want a good, solid, athletic defensive lineman. We want a cornerback who can cover, not one who can just play zone. We'd gamble a bit at wide receiver and take a fast guy who might be a bit of a sleeper, rather than taking a steady type of performer. We would take a tight end who can block but we'd prefer one who was a move guy, an athletic type with body control and good hands. We'd sacrifice a little speed to get one."

The draft starts at 10 a.m. today, with New England, going first, expected to make Kenneth Sims, the defensive lineman from Texas, its No. 1 selection. After that, the order of drafting will depend on what comes from the trade talks going on yesterday involving Los Angeles, Chicago and Baltimore.

League sources presented the following scenario: Los Angeles wants Colts quarterback Bert Jones, but has been unwilling to give up the No. 4 pick in the draft for him, offering instead another first-round choice, No. 14, obtained last year from the Redskins.

So yesterday, the Rams reportedly were trying to sign quarterback Vince Ferragamo, who played in Canada last year, then trade him to Chicago for a second-round selection. They then would trade their No. 4 in the first round, and a second-round pick, for Jones and give No. 14 to New England for tight end Russ Francis, who did not play in 1981.

Two Baltimore assistant coaches worked out Ohio State quarterback Art Schlichter yesterday for the second time, anticipating that Jones would be traded and that the Colts would have to choose either Schlichter or Brigham Young quarterback Jim McMahon.

Other quality players sure to be taken early in the first round include linebackers Johnie Cooks of Mississippi State and Chip Banks of Southern California, guards Sean Farrell and Mike Munchak of Penn State and Roy Foster of Southern California, running backs Walter Abercrombie of Baylor, Marcus Allen of Southern California, Darrin Nelson of Stanford and Gerald Riggs of Arizona State, defensive lineman Glen Collins of Mississippi State and wide receiver Anthony Hancock of Tennessee.

Some of the Redskins' 1982 plans depend on the draft's outcome. Gibbs said he is not sure safety Mike Nelms will be moved to wide receiver, as planned, especially if a receiver is picked today. If that happens, Gibbs said, Nelms will be given "every chance possible" to beat out safeties Mark Murphy and Tony Peters "because we must get more aggressive on defense and Mike is one of our most aggressive players."

The team also has not decided whether to stay with a 4-3 defense or switch to a 3-4. "I want to see who we draft first," said Petitbon.

The Redskins already feel they have a head start on this draft, since a number of 1981 selections who either never made the active roster last year or have changed positions will be available for this summer's training camp.

"(Linebacker) Larry Kubin and (defensive lineman) Darryl Grant have a chance to start," Gibbs said. "We still think (receiver) Charlie Brown can play and we have to take a good look at (guard) Gary Sayre and (tight end) Clint Didier."

Kubin, a sixth-round choice last year, spent the season rehabilitating an injured knee, but was projected as a second-round draft choice before he was hurt. Grant (ninth round) has been moved to defense from guard and Gibbs is pleased with the switch. Brown (eighth) and Didier (12th) were on injured reserve last year. Redskins Sign Five

The Redskins yesterday signed five free agents: Willie Olley, a 5-foot-10, 185-pound cornerback from East Carolina; Johnny Stoutamier, a 6-2, 180-pound cornerback from Livingstone; Frank Carr, a 6-foot, 185-pound wide receiver from North Carolina A&T; Ed Jackson, a 6-4, 265-pound defensive end from Maryland-Eastern Shore, and Rod Salate, a 6-3, 210-pound punter from Illinois State.