The midfielder believes that, ahead of the striker's expected move from Napoli, the Uruguayan could form a "wonderful" duo with Zlatan Ibrahimovic
The Napoli striker had been attracting interest from the likes of Chelsea, Real Madrid and Manchester City but none would bid as high as his €63 million contract clause.
However, PSG are believed to have come closest to the Serie A side's valuation of Cavani and reports in France suggest a deal could be completed as soon as Thursday.
Motta, 30, told Le Parisien on Wednesday: "He is very strong. He works hard on the pitch while scoring a lot. He is a real centre forward on which we can rely.
"If a transfer were to happen, it would be a great thing. He has done so much for Napoli and Uruguay. Cavani could help Paris to grow."
The Brazilian also talked up the prospect of the 26-year-old Uruguayan partnering up in attack with Zlatan Ibrahimovic, who took Ligue 1 by storm in his debut PSG season by firing in more goals than any other player to help the club take the title.
"They are very strong," he added. "An Ibra and Cavani combination would be wonderful for Paris. But I do not want to talk too much about him as it is not official. For now, he is still a Napoli player."
The midfielder is not bothered by newly promoted side Monaco following PSG's tactic in recent transfer windows by spending big to fashion a formidable outfit and believes the competition between the two sides will benefit Ligue 1.
"It's beautiful," Motta added. "This will make a large part of the world watch more French football. It will be good for all.
"But, although I hope it will become a major event, it will take time for a PSG-Monaco rivalry to reach to level of Barcelona-Real Madrid or Bayern Munich-Borussia Dortmund. The future looks exciting for French football. It's great what is happening in France."