OH NO I MISSED THIS QUESTION IM SORRY ANON i haven't read anything long for these two in a while actually but i can recommend some stuff that i still remember :D

MY ABSOLUTE FAV it's so simply amazing i adore scam email jokes and this is the joke that evolves into something that gave me serotonin. short: rich boy diluc gets scam email from khaenri'ah prince
https://archiveofourown.org/works/27278782

political mindgames and arranged marriage:
https://archiveofourown.org/works/31069238/chapters/76756694

just really good classic luckae:
https://archiveofourown.org/works/27724420

graphic designer kaeya. that's it i just feel that (i think that was luckaeluck but it had no smut?)
https://archiveofourown.org/works/32098810

there are some wild reincarnation fics but those are kaeluc tagged so i won't include them
if you want more mature (and spicy) themes please check out the Horsebreaker/Kingmaker by https://archiveofourown.org/users/JulesAS it's a masterpiece and their mind is huge and i really can't say anything more but it will alternate your brain chemistry forever

I hope I'm not too late! Hope you'll find something new and maybe enjoy it ;u;