I want to believe that "Jaycee" will return as a character with a variation of the Xing Yi fighting style incorporated with Lucha Libre while Michelle returns as a character laced with the more fundamental aspects of the same fighting style
(like how Kazuya, Devil Jin, and Heihachi vary their own fighting styles in game play).
To be a little more specific, picking between "Jaycee" and Michelle in the predecessor (TTT2) was like apples and oranges:
The daughter has more versatility and (particularly) useful gimmicks in her move set while the mother is a slightly nerfed BR Julia.
The reason why one would play Michelle over Jaycee is because of Mad Axes and the stronger whiff punishment options. The tradeoff is that Jaycee has a easier time "partying" at the close range and "getting in" on the opponent as well as dirty tricks (i.e BT mix ups, f3 into mid kick launcher/throw, f2+3 for a relatively safe way of getting in, uf2 low crush "super girl" punch, and having better okizeme options than Michelle... and little more as those were only the few examples that I could come up with). I want to believe that both of them will somehow make it (which I strongly doubt at this point to be frank. But, I still want them back because.... reasons XP).