Okay but the royal au where WWX gives birth in prison. By sheer shit luck, or the stress of the pregnancy, or a mistake/'mistake' during delivery, A-Yuan is stillborn - but with golden eyes, with the Lan mouth; it couldn't be more obvious whose child he is.
WWX has just barely been hanging on this whole time and upon hearing that his A-Yuan, his baby is dead, he just goes catatonic. He won't respond to anyone, to anything, won't move - just stares blankly into space.
LWJ gets the news that his disgraced consort has given birth - to a stillborn son, A-Yuan, with the Lan golden eyes and the Lan mouth, and while physically well, WWX hasn't said a word or moved since he was told that his son - their son - was dead.
Immediately he rushes down. Part of him hopes that WWX will respond to him, but most of him knows better. And sure enough, WWX just stares through him. He's been cleaned and is recovering physically - but fine, LWJ can work with that. Their son is dead, but WWX is still alive. He's just in shock. It'll pass, and LWJ can make amends, and they can try again.
A-Yuan is buried with all the honours of a crown prince, laid in his grave by the Emperor's own hands, incense and paper offerings burned for him so that he might be cared for in the afterlife. In all this time, the only times LWJ has touched his son was when he was in the swaddling that became his funeral shroud, or in his coffin.
LWJ has WWX moved to the Empress' chambers and cared for, and after a few days have passed with no change, sends for JYL and JWY in hopes he'll respond to their voices.
It's a very near thing, but JWY does not, in fact, gut the Emperor for having the gall to mistreat his brother into this state and then summon JWY to try to help him make amends. JYL is contemplating assassination, but focuses her efforts on the immediate crisis, the job that is productive:
That it has been weeks since WWX gave birth, and in all that time, he has not moved, spoken, or responded to anything or anyone around him. But he might respond to his foster didi, to his foster jiejie who he loved so much.
At first they try to call him out of his catatonia, holding his hands and talking to him. Won't he greet his siblings? His jiejie is here, she's come all this way to visit her Xianxian. And A-Cheng is here too, he's missed him, Lotus Pier just isn't the same without his endless troublemaking.
(If, privately, individually, Jiang Cheng and LWJ each offer to get WWX away from LWJ, spirit him away or divorce him and make it so that WWX never has to see LWJ again, that's fine, that's their own business)
It switches to pleading, Xianxian, you're scaring me.
Wei Wuxian, you're making jiejie cry, damn you, say something, do something, even blink, or I'll -
Wei Ying, please. Even if it's just to say get lost, say something. It's alright if you hate me, as long as you respond. You don't have to see me ever again, you just have to say it.
The Emperor refuses to take another consort until WWX wakes and tells him to himself.
(how this ends is a big ?????. WWX might conveniently die during the night, clearing the way for a new consort, or mysteriously disappear around the same time a room in Lotus Pier becomes closed to all but the Jiangs and a couple of servants. Or WWX might wake up and refuse to speak to LWJ ever again - he becomes the first case of an imperial divorce where the consort made it out still honoured.)
(And yes, the pleading part was meant to be JYL, JWY, and LWJ respectively. Only JYL still calls him Xianxian, and JWY can't bring himself to threaten to break WWX's legs.)
I'm just picturing WWX having a massive break down after weeks or months of nothing. Maybe they take him to the babies grave and he starts screaming and wailing and cursing at all of them.