The position of Gian Piero Ventura is also far from certain, with Italy needing to overturn a 1-0 deficit to Sweden in their World Cup play-off if they are to avoid missing out on a place at the finals for the first time since 1958.
Italy reached the quarter-finals of Euro 2016 under Conte, where they were knocked out on penalties by world champions Germany, and Del Piero admits he would love to see his old team-mate come back to the national team.
"He did great with Juve of course and a great job with the national team," Del Piero told Sport360.
"We would love to have him back in Italy, of course, because he is a great coach. He would improve any team and this is what he did with Chelsea last season and what he did with Juve as well.
"We had some problems and he fixed it, then won the title. He has some amazing qualities and that's why he's coaching the best teams in the world. I hope he will have a great period with Chelsea and then maybe one day come back."
Italy face Sweden at San Siro on Monday amid great concern about a lack of attacking strength, with the Azzurri having failed to score more than one goal in a single game since a 5-0 win over Liechtenstein in June.
Del Piero, however, feels it is only a mental concern that is holding back the forwards.
"[Ciro] Immobile seems to be scoring every week," he said. "He's amazing for that, so Ventura has real options. He has [Lorenzo] Insigne and [Antonio] Candreva on the right side so I don't think we have a problem with the options in attack.
"There is no forward who is not playing well but the problem is maybe mentality."