Swiss captain Severin Luethi picked Wawrinka (ranked 17th best player in the world), Marco Chiundinelli (148th), Henri Laaksonen (291st), Michael Lammer (360th) and Sandro Ehrat (353rd) to help the central European country win the elusive cup.
Switzerland has never won the Davis Cup, although was runner up in 1992.
Swiss tennis great Federer, a 17-time Grand Slam winner, has repeatedly in the past prioritised other championships over the Davis Cup.
He had already cautioned there was little chance of seeing him on the court during the first round of the cup in Geneva from February 1st to 3rd, so shortly after the end of the Australia Open.
The world number two, who drew fire from Wawrinka, could meanwhile still change his mind.