No, Katey Sagal was not in the cast list of Edward Scissorhands.
You might be talking about Kathy Baker who played Joyce, Tom Jones-listening housewife with creepy fingernails. Her character has a great resemblance with Katey Sagals character Peg Bundy (Peggy Bundy). This is probably because the characters of Joyce and Peggy are seductive.
Kathy Baker has been strangely denied all-out stardom, yet continues to demonstrate her versatility in whatever material comes her way.
As popular and identifiable as her Peg Bundy persona was, Katey Sagal on the other hand assertively moved on without a hitch after the show went off the air, not only starring in other sitcoms and television movies, but portraying characters that were polar opposite to the outrageous role that first earned her nationwide attention.
Tip! View Gloria VanderbiltKatey Sagal's and Kathy Baker's Filmography and on IMDb.