I'm not sure. As others have pointed out: She lacks experience in five round fights, and did not look the same after her return. She's been plagued by injuries and lost a lot of time due to them. She's also never fought anyone with Weili's combination of athletism, strength, experience, striking and grappling skills. Let's not forget Weili has fought five rounds FOUR times in the UFC as well.
HOWEVER, Weili has fought only once two years in a row, is getting up there in age for MMA standards, and hasn't faced anyone with the top control that Tatiana has. She leveled up her grappling immensely, but her cardio has suffered from it as shown in her last fight with Yan Xiaonan.
I think it's going to be a fun fight, that more than likely will be a grappling heavy fest going the distance instead of ending via finish as most expect. I'm not confident in picking either of them, but I'll never forgive Weili for knocking out Joanna like she did, so I wouldn't be mad if Tatiana mauls her.