Honkai Impact 3: Memories exposed, did I really go to save the world?

Also known as: Collapse Exposure: Opening up the Destiny and Crossing the Imaginary Tree
[Honkai Impact 3rd series + semi-invincible + some private settings + exposure flow + multiple female protagonists]
(Note: No original CP! The main world collapses three)
As a child, Lingfeng suddenly gained the ability to travel through the world and also obtained an exchange-type panel.
At the age of 7, he accidentally traveled through a fairy ship and became a disciple of Jingliu, where he learned Jingliu's true swordsmanship and embarked on a path of destruction. At the age of 17, he participated in the Third War of Plenty as a general.
After traveling again, he became a member of the Star Train.
Lingfeng suddenly disappeared from this world for a full thirty years.
With the rapid development of technology in the past thirty years, various countries have joined forces to create a memory viewer. As long as the missing person's belongings are placed on it, the missing person's experiences from the past to the present can be explored.
This machine is used in an entertainment program called "The Unknown Secret". Every time it is broadcast, tens of millions of people watch it. It has always been at the top of the entertainment charts and is the most talked about program.
Until one day, a woman placed a piece of her son's belongings that had disappeared more than 30 years ago on the instrument, and the entire Internet was immediately in an uproar.
It’s no secret that he carries the world on his shoulders.
Everyone knows about his attack on the Tree of Illusory Numbers~
Ling Feng placed one hand on a huge golden tree (the Tree of Imaginary Numbers), and turned towards the train that crossed the galaxy.
"This is... our way home!"
A few days later, several letters were suddenly found at home.
"Who is Fu Xuan? What is the nameless guest badge?"
"Who is Hanabi-sama?!"