Traveling through Gensokyo, but the system is Jujutsu Kaisen?

People in Gensokyo have a Jujutsu Kaisen system and possess all the abilities within the Jujutsu Kaisen system.
Just when Xiangbei thought he could punch the Red Devil Kindergarten and kick the Forever Nursing Home and live a carefree and peaceful life, he found that something was wrong with the Gensokyo he traveled to.
Why did Alice have another daughter, and why was she named Ai Ge?
Why can Rumia grow up, and why does Reimu have a foster mother who calls her grandma?
Why is there a girl named Yakumo Kurenai in the hidden historical traces of Gensokyo?
It was far more than that. The deeper he went, the further north he found himself from a peaceful life...
Also, isn't this stitched-together fanfiction a bit too much? !

(Fan fiction, third- or even fourth-creation works that stitch together a large number of fan fictions, will have plots similar to the world.)
(The fan works that have been stitched include Fantasy Village Player, Little God of Fantasy Village, Touhou Young Reimu and Reimu)
(It is expected that the more well-known Touhou fan works such as Love's Bizarre Adventure and Touhou Alien Village will be stitched together)
(If I have to say, Gensokyo players actually account for a larger proportion)