This is most likely in reference to her very limited role in The Rise of Skywalker, which was much smaller than in the previous installment. A scene featuring a conversation between Rose and Rey was also seemingly cut, reducing her role even further. For Tran to return to the role, it appears that it would be extremely necessary for Lucasfilm and Disney to give a significant and worthy role for Rose Tico in the hypothetical series.
In an interview with Collider, Kelly Marie Tran responded to questions regarding whether she would be interested in reprising her role as Rose Tico.
After being asked about the possibility of reprising the role of Rose Tico in a Jon M. Chu-led Disney+ series, Tran said:
He’s so cool. I don’t know. I honestly don’t know. It’s so strange. I had so much fun being in that world but I feel like the pieces would have to fall into a perfect little puzzle and everything would have to feel like it’s the right time and the right moment and the right story, like with any other project. But I don’t know.
The interviewer then stated that Rose is a character that has “more story to tell,” to which Tran agreed:
Yeah, absolutely. Absolutely. I think there are a lot of characters in that universe that we have yet to hear enough about.