Lucifer isn't like canon and actually rules hell. Lilith, since we know very little about will be OOC if she's revealed in the show, as I'm basing my interpretation of her off of what is said by viziepop in past streams.
Charlie will act differently as well since she will have an older sister and thus someone else besides her mom who will support her.
Will add my own HC and lore since so much remains unknown. If I have to rewrite something once season 2 drops, I will.
Also, MC looks is on the cover, and the dress is what she wears at Charlie's birthday Banquet. The hairstyle differs, but her horns do look similar to the cover and can change shape. She just usually leaves them like that because she doesn't want to confuse people more with her similar looks to Lilith. Heavy AU as I will be changing quite a few things, which conflict with the ending of season 1 and also its first episode
Having watched and finished season 2, I am very dissatisfied with how Lucifer was treated and how Charlie acts. So, season, besides a few things, will not be canon in my fics. AU and Lucifer can harm sinners, but not personally; but use proxies or have their eldest, aka Evelyn, who gladly does so, handle them. And since Evelyn has changed things, hell and its sinners will be far more well-behaved and respectful of the royal family. Lilith isn't in heaven in my au, and in the newest chapter, quite a few things will be explained or altered.