wei wuxian isn’t actually dead, he’s hiding in ghost city!
he accidentally finds out he can use his flute to make hua cheng do things because he is. in fact. also a ghost.
he doesn’t make hua cheng do anything too much at first, just joking around making him dance embarrassingly in public or flip off the wrong people.
and then in walks xie lian. hua cheng is insistent on being the self deprecating clueless lovely idiot we know him as.
wei wuxian decides to take it upon himself to be the #1 wingman ever and speed up the process by getting them together with the power of flute playing!
eventually hua cheng also convinces wei wuxian to return to the land of the living for lan wangji!
wei wuxian: bro he obviously is in love with you! full on flirt with him! stop being so cryptic!
hua cheng: mmhm ok whatever you say… and what about you and that one guy you knew? what was his name? lan-
Thinking about Wei Wuxian's first meeting with Jin Ling again and how fucking funny and delightful it is. Like, let's put the "WWX, you probably could have EASILY guessed this was your nephew if you had spent just thirty seconds thinking about this person's identity" aside completely for a moment. Let's just pretend here that Jin Ling isn't even his nephew. Not a factor.
Wei Wuxian is still in the body of MO XUANYU, who was kicked out of the Jin Sect in disgrace and resorted to sacrificial rituals to commit murder. He KNOWS this. He KNOWS that Mo Xuanyu and the Jin Sect have a bad history and that the Jin Sect considers him an utter embarrassment that they want nowhere near them, and that powerful people will enforce these things with violence. He WILL be recognized (Jin Ling recognizes his crazy uncle Mo Xuanyu immediately) and any actions he takes here will probably be noticed and reported on. Publicly starting shit as Mo Xuanyu especially may cause the Jin Sect to angrily hunt him down later.
So, like, it makes sense to be cautious! The Jin Sect were his enemies in his last life, too, and even if Mo Xuanyu had ZERO relation to the Jin Sect whatsoever and was a complete stranger to them, Wei Wuxian should want to stay out of their way lest they somehow learn that the Yiling Patriarch is back. It's very reasonable to assume that the Jin Sect would raise a new killing mob against him immediately. Wei Wuxian doesn't really know the current political landscape at all, and so it would be smart to stand back, observe the hunt for a little bit, and avoid interacting with the Jin Sect at least for a little while.
All it would take is Wei Wuxian standing back while this fuss with the hundreds of spiritual nets accidentally catching other cultivators happens. He could just hide behind a tree, let Jin Ling and his entourage go by him, and try to find some other way to get the poor people down. All it would take is Wei Wuxian NOT calling out a Jin Sect cultivator for being a "spoiled rich brat".
I love how petty lan wangji is like he has this mask of indifference but on the inside he's noting down every slight to the people he cares about and waiting patiently to enact revenge. The only people who know are his brother and Wei wuxian and even then their petty too so they find it hilarious.