from what I have read on the subject, as far as the PR universe is concerned Trini as well as the others. Zack and Jason. (i think they were the only ones to leave at this point I could be wrong) gave their powers to the next generation of rangers.
after that point if I recall Thuy went back to get her civil engineering degree, however one day on the way back from a wedding rehersal if i remember, for her friend. the car Thuy and her 2 friends were in lost control smashed into a roadside barrier and flipped over the railing settling at the bottom of a hill.
So in closing as far as Trini dying. in the PR universe I suspect she and the others returned to normal life as it was, while the next gen. of rangers took over.