The Italian Olympic Committee's anti-doping prosecutor recommended Friday that Kostner be banned for four years and three months.
The request was made as part of a widespread doping inquiry set off when Schwazer tested positive for EPO before the 2012 London Games
Kostner's lawyer said following a CONI hearing in September that the skater had nothing to do with Schwazer's doping, but prosecutors believe she helped the walker avoid a drug test.
The case will now be decided by CONI's internal doping court.
The 27-year-old Kostner, the 2014 Olympic bronze medalist and 2012 world champion, is taking this year off from competition but a long ban would rule her out of the 2018 Olympics in Pyeongchang, South Korea, and could end her career.
Schwazer, who won the 50-kilometer walk at the 2008 Beijing Olympics, was excluded from the London Games after testing positive before the games.
The CONI prosecutor also recommended bans for three of the four members of the Italian squad that won the silver medal in the 4x100-meter relay at the 2010 European Athletics Championships: 27 months for Simone Collio, 24 months for Maurizio Checcucci and eight months for Roberto Donati.
Emanuele Di Gregorio was the fourth member of the relay squad that took second behind France at the event in Barcelona. Germany finished third.
The CONI case is based on input from a prosecutor in Bolzano investigating the Schwazer file, which has allegedly uncovered widespread doping within the Italian athletics federation.
Prosecutors believe coaches and doctors knew that Schwazer was doping long before he tested positive, possibly dating to Beijing. He was banned by CONI for 3 1/2 years in April 2013.
The CONI prosecutor also recommended a three-month ban for Schwazer's former coach, Michele Didoni, for failing to show up at a hearing.
Kostner also skipped a hearing at CONI in September before showing up a week later.
Schwazer failed an out-of-competition test before arriving in London and was removed from Italy's team before competing. He admitted using the blood-boosting hormone EPO, and said he was quitting the sport.
Schwazer also admitted to consulting with Lance Armstrong's banned sports doctor, Michele Ferrari.
Kostner has acknowledged accompanying Schwazer on a visit to Ferrari's office in 2010, although she maintains that she did not know he doped.
However, published reports of Kostner's testimony to Bolzano prosecutors showed she allegedly admitted lying to inspectors from the World Anti-Doping Agency who came to her home in Germany looking for Schwazer on July 29, 2012 — days before Schwazer flew to London for the Olympics.
According to Kostner's lawyer Giovanni Fontana, the skater told inspectors that Schwazer wasn't home because she wanted to respect his privacy, saying that on his WADA whereabouts form for that day he had listed that he would be available in Italy at a different time.
Ultimately, the WADA inspectors caught up with Schwazer in Italy and that's when he tested positive.
Kostner has also won two silvers and three bronzes at the worlds, and is a five-time European champion. It remains unclear if she could be banned retroactively and stripped of medals.