Well, usually such crossovers involve the trainers having to adapt to different rules and cultures of the new world. They might also gain new skills or powers to survive and thrive there. Another common thing could be meeting unexpected allies or foes.
Often, you'll find unique challenges and adventures that the trainers face in the unfamiliar world. Maybe there are new creatures or magical elements they have to deal with.
In these fanfictions, it's common for the trainers' existing skills and knowledge to be tested and expanded. Also, the exploration of the new world's landscapes and mysteries often plays a big part. Sometimes, there are even hidden secrets or quests that only the trainers can uncover.
Chapter 347, "Mirror Valley Council, Power Surge, Dajue Temple, Eight Battalion Tournament", is the clearest early answer because it turns Xia Chuan's situation into a concrete plot event. The setup is As the first station in the Great Xia's expansion, Mirror Valley..., but the pressure keeps building through It is the first transit point for Great Xia's northward entry into....
Chapter 346, "This person doesn't seem to like her very much", 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 Yes," Jiang Li said, "I learned that this 'Night Walk' is an...
Chapter 106, "The Beginning of the Butterfly Effect", is the clearest early answer because it turns Butterfly Effect Thinking's situation into a concrete plot event. The chapter turns that into something concrete by moving from Thinking of this, He Yun nodded with a hint of anticipation.
Chapter 341, "Moao's Nine Garrisons, the Inspection System and Zhenyu, Li Hu and Hong Yuru (Part 3)", is the clearest early answer because it turns Beining Mountain's situation into a concrete plot event. A useful checkpoint is the way the scene starts with Of course, just this alone is not enough to deal with He Wuyang. and follows through with As for their Defensive Army, I saw three units, though I'm sure there....
Chapter 144, "She's Too Bullying!!!", is the clearest early answer because it turns Aunt Ying's situation into a concrete plot event. It opens with Ordinary people would have been at a loss in this situation by now. and closes on He then noticed the hand—fair and slender, not at all like an....
Chapter 48, "All the Bitter Teas Have Been Taken Away", is the clearest early answer because it turns Bitter Teas Have's situation into a concrete plot event. Early on, He Yun felt guilty for initially ignoring Jiang Li on purpose, and....
Chapter 114, "I've never seen someone so shameless!", is the clearest early answer because it turns Jiang Yan's situation into a concrete plot event. The chapter gives readers a real answer by opening on As time passed, the number of viewers in the live broadcast gradually...
Chapter 275, "Five Defects and Three Shortcomings", 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 Hu Zi was exceptionally cooperative, and within half an hour, all the...
Chapter 240, "He's the Last One?!", is the clearest early answer because it turns Jiang Yan's situation into a concrete plot event. The chapter gives readers a real answer by opening on Wuuuuh He Bao truly deserves it, Mom always knew you could do it!"...
Chapter 127, "He's Not Snobbish, Just Simply Bad-Tempered", is the clearest early answer because it turns Jiang Yan's situation into a concrete plot event. The chapter turns that into something concrete by moving from Witnessing Jiang Li leave with a bucket, Jiang Yan refused to admit...