maybe try:
http://www.mangago.zone/read-manga/ebony/
http://www.mangago.zone/read-manga/the_villainess_lives_twice/
I'm not sure if it's what you mean because I haven't read Grandfather of Demonic Cultivation but I feel like in these 2 manhwas the female leads are both really strong and intelligent.
It's a lovable rogue kind of trope, and the 2 ML have a sort of close-since-forever dinamic, where they work together without words, or do naturally small caring things like ordering food they like or knowinng they have trouble socializing and avoid crowded spaces....No akwardness....Another similar one would be This girl is a little wild (but there hasn't been updates since foreveeeer)
Soooo.... I just read Grandfather of Demonic Cultivation....And I really liked Wei WuXian's character, brave, flawed, fun-loving, driven to be the best. And his relationship with Lan WangJi that was based on trust, friendship, desire and care. So my question is: are there any manga, manhwas, novels with this dinamic/ character, but female? The best I can think of is Beware the Villainess, where Melissa is that cool fun unnie you want to be/ date.