"If there's any truth to the rumors, I'd just be really excited because I'm a huge fan," Levine told reporters after Monday night's live show kickoff. "She's a wonderful human being. I love her to pieces. So talented."
Host and producer Carson Daly also heaped praise on Stefani, but seemed to want to manage expectations about whether she'll be the one to replace Christina Aguilera.
"She would be great," Daly said. "These things are tough to work scheduling-wise. I don't know where we're at with it."
Aguilera, who is currently not coaching this season, was originally scheduled to head back to the panel for season 7, but is now taking time off while she's expecting a baby with fiancé Matt Rutler.
Stefani, 44, welcomed her third son with husband Gavin Rossdale on Feb. 28, and Daly didn't say whether mom duties might prevent Stefani from signing on.
"I hope it becomes confirmable, but I don't know," he said. "But she certainly fits that bill, that shortlist of what we have to be a good coach on the show, which is somebody who's got some experience and who's on top of their game."
As he also points out, she's got a personality that could benefit the contestants – and her potential fellow coaches.
"She's just a great mother, she's a great person," he said. "She's friends with the other coaches but has a strong opinion, which is also important. They can't all just be too lovey out there. So I think she'd be a solid choice."
One person who stopped short of singing Stefani's praises? The always competitive Blake Shelton.
"I've never actually met her," he said. "I know who she is and I know some of her music, and I look forward to beating anybody on this show, honestly."
Reporting by GABRIELLE OLYA