There are quite a few out there. You can check out fanfic platforms like Archive of Our Own. Just search for'star butterfly crossover' and you'll find a variety of stories. Some might focus on the adventure aspect, while others on the more emotional relationships between characters.
One that I've heard is quite good is 'Star and Butterfly: The United Worlds'. It delves into how the two main characters from their respective shows come together to face a new threat that endangers both of their universes. It has great character development and some really cool plot twists. Another one is 'The Crossover of Magic' which explores the different magical abilities of the characters and how they can be combined in unique ways.
Look to Chapter 81 for the clearest answer. It begins with Qi Tianyu, who chose curry beef rice, received a piece of curry and a..., keeps building through Shu Yan was relatively lucky, she got a bundle of noodles and a bag of..., and lands on The summer on the Southwest Plateau is no joke;
A practical answer is Chapter 55, because it turns the idea into a concrete scene. The chapter opens with Su Yinwan hadn't expected that, in just one day, Jiang Li's reputation had..., adds pressure through This person was even a top gaming streamer with tens of millions of fans,..., and ends on.
A practical answer is Chapter 15, because it turns the idea into a concrete scene. The chapter opens with Jiang Shixu woke up from those nightmares filled with blood and darkness,..., adds pressure through Jiang Shixu's mind was starting to cloud, but for some reason, when he..., and ends on Since.
Look to Chapter 85 for the clearest answer. It begins with Facing everyone's skepticism and curiosity, Jiang Li explained fluently:..., keeps building through The tomatoes are grown by them, and the eggs are also from their..., and lands on This fresh and vibrant flavor blended perfectly..
Look to Chapter 23 for the clearest answer. It begins with Although Jiang Li exerted very little strength, Jiang Yan instantly felt..., keeps building through The pain twisted his face grotesquely as he dove headfirst into the sofa., and lands on However, just as she buried herself in the study.
If you want the clearest chapter reference, go to Chapter 47. Early on, Qi is actually second???] [Did the production team make a mistake?; later, the chapter leans on Isn't Qi supposed to be first?] [So who's first?.
The best chapter pointer here is Chapter 74, "Ordinary People". It opens with Having seen Jiang Li's ID before, he knew that this person named Shiguang... and closes on The man's phoenix eyes narrowed slightly, he looked at the girl sitting....
Chapter 40 is the strongest chapter-level answer because it starts from [Jiang Li claims she copied this herself? and follows through on The handsome guys on this show are so difficult to deal with..
Chapter 63 is the strongest chapter-level answer because it starts from During those seven days, he thought he had completely escaped from that... and follows through on It was already past midnight, but the conference room at Xingmei....
The best chapter pointer here is Chapter 36, "The Coldest Variety Show Opening in History". It opens with But soon, people began to question the authenticity of Jiang Li's bare... and closes on After swallowing the food in his mouth, he hurriedly took his megaphone....