He might meet a powerful wizard who is the ruler of that dimension. This wizard could initially be hostile towards Natsu, seeing him as an intruder, but later they could become allies.
Natsu could meet a group of rebels in the new dimension. These rebels are fighting against an oppressive regime in that dimension. Natsu, with his sense of justice, would likely join them in their fight. He would also learn about their unique culture and way of life during this time.
There's a chance that Natsu meets a strange being that has the ability to manipulate time in the other dimension. This being could either help Natsu by sending him back to his own dimension or cause him more trouble by sending him to different points in time within that dimension, creating a complex and exciting adventure for Natsu.
Chapter 496, "Hot Pot Tonight!", is the clearest early answer because it turns Hot Pot Tonight's situation into a concrete plot event.
Chapter 341, "Whose Child Is Jiang Cheng Really?", is the clearest early answer because it turns Li Ruofang's situation into a concrete plot event.
Chapter 457, ""Back Against the Wall", is the clearest early answer because it turns Jiang Li's situation into a concrete plot event.
Chapter 433, "The Young Master Has His Own Ideas", is the clearest early answer because it turns Jiang Zhao Yuan's situation into a concrete plot event. The chapter turns that into something concrete by moving from Since Jiang Yan and his group left, the house had become much colder.
Chapter 83, "Can Actually Carve Flowers?!", is the clearest early answer because it turns Flowers's situation into a concrete plot event. The chapter turns that into something concrete by moving from When they received the task, the three of them were already...
Chapter 444, "Wait and See", is the clearest early answer because it turns Dean Yu's situation into a concrete plot event. The chapter gives readers a real answer by opening on Carrying a backpack, Yu Li walked for over ten minutes but ultimately...
Chapter 190, "Aren't We Friends?", is the clearest early answer because it turns Jiang Yan's situation into a concrete plot event. Early on, Several people who didn't understand fell silent.. By the end, Because he saw the pack of cigarettes pinched between Jiang Li's....
Chapter 627, "Definitely Not an Accident", is the clearest early answer because it turns Don's situation into a concrete plot event. The chapter gives readers a real answer by opening on He looked at the sinister smile lingering in Jiang Li's eyes, then at...
Chapter 189, "Do You Still Like the Gifts from the Program Team?", is the clearest early answer because it turns Like's situation into a concrete plot event. The chapter gives readers a real answer by opening on Seeing his painstakingly planted roses trashed like this, even as a...
Chapter 228, "Younger Brother is the Number One Hater?!", is the clearest early answer because it turns Mr's situation into a concrete plot event. Early on, Huo Ziyang had not stepped out of the house for a whole week..