You could also check out some Star Trek - focused fan forums. There are often threads where fans share their own fanfictions or recommend ones they've read. By asking specifically about 'Bella dresses as Deanna Troi' fanfiction in these forums, you might get some direct links or tips from other fans who are into the same concept.
You can try searching on popular fanfiction websites like Archive of Our Own (AO3). They have a vast collection of Star Trek - related fanfictions, and there's a good chance you'll find something with Bella dressing as Deanna Troi there.
Another option is FanFiction.net. It has been around for a long time and has a large community of writers and readers. Just use the search function and type in 'Bella dresses as Deanna Troi' to see if there are any relevant stories. However, the quality can vary greatly, so you might have to do some sifting through the results.
Chapter 74, "Ordinary People", is the clearest early answer because it turns Jiang Li's situation into a concrete plot event. The chapter turns that into something concrete by moving from Having seen Jiang Li's ID before, he knew that this person named...
Chapter 339, "Today's Windfall Luck!", is the clearest early answer because it turns Miss Jiang's situation into a concrete plot event. The chapter gives readers a real answer by opening on The models had already stopped their runway walk when they heard the...
Chapter 226, "Live Fortune Telling!", is the clearest early answer because it turns Sister Li's situation into a concrete plot event. Early on, What was all that before then?. By the end, Are you sure you can be on the list of winners?] Zhou Xu: [?.
Chapter 397, "Talent Show Program", is the clearest early answer because it turns Youth Trainee's situation into a concrete plot event. The chapter turns that into something concrete by moving from Second Aunt, I know you're worried about Shixu interacting with...
Chapter 510, "The Fake Young Master", is the clearest early answer because it turns Gu Group's situation into a concrete plot event.
Chapter 181, "Are All the Weibo Followers Police?", is the clearest early answer because it turns West District Police's situation into a concrete plot event.
Chapter 243, "How Could It Be Her?!", is the clearest early answer because it turns Southwest Plateau Airport's situation into a concrete plot event. Early on, Hahaha, the young master's face has gone white, but I got a scare....
Chapter 183, "Sacrifice Oneself, Break Them Up!", is the clearest early answer because it turns Jiang Li's situation into a concrete plot event. A useful checkpoint is the way the scene starts with Seeing that he held a blue ball identical to Su Yinwan's, Jiang Yan...
Chapter 349, "Everyone Who Went Out to Dinner that Night Got Poisoned!", is the clearest early answer because it turns Shang Shaojing's situation into a concrete plot event. It opens with The news quickly reached Ye Chu. and closes on Let alone the situation with the Gu Family....
Chapter 298, "Turning the World Upside Down", is the clearest early answer because it turns Jiang Cheng's situation into a concrete plot event. Early on, Grandfather, I, I can testify, everything Sister said is true." Right....