Tate (18-6) is very familiar with both Rousey and Nunes. She fought Rousey twice, in 2012 and 2013, and coached against her on a reality television series. In July, Tate lost the 135-pound title to Nunes at UFC 200 in Las Vegas.
Tate has a big fight on her plate against Raquel Pennington (8-5) at UFC 205 on Nov. 12, but was willing to share her opinion on Rousey's comeback title fight with ESPN.com.
"I think if Ronda is at her height, I would probably say Ronda [wins]," Tate said. "I always tend to favor grapplers. That's just my bias. I think it's more probable for a fight to go to the ground and get finished than it is for a clean knockout. That's less common in women's MMA.
"So, if you factor that in, I think Ronda is the stronger grappler."
Rousey (12-1) is a U.S. Olympic bronze medalist in judo, with nine career submission wins in mixed martial arts. Nunes (13-4) has won nine fights by knockout. Rousey is the betting favorite.
Tate said she's not extremely confident picking Rousey, however, as she has questions regarding the former champion's mindset. Rousey hasn't fought since she suffered a vicious knockout loss to Holly Holm at UFC 193 in November 2015 and has mostly stayed out of the spotlight during that time.
"What's so weird about this fight is all the X factors," Tate said. "Amanda is a really tenacious fighter and I think she's going to have a newfound confidence coming into this fight.
"I guess what I don't know is how Ronda is going to show up. I'm pretty confident about what Amanda will show up, but Ronda -- it has been such a long time. Ring rust can be a very real thing and how is she going to be as far as being punch-shy? She knows Amanda is heavy-handed and after being cracked by Holly, does that change the mindset of someone like Ronda who kind of believed, along with many others, she was untouchable?
"It's hard to say who wins this because it kind of depends on what version of Ronda shows up."