Books with mature writing style but YA plot

I was a huge reader when I was in elementary/middle school, stopped in highschool because of assigned readings, and am recently trying to get back into reading in my mid 20s.

I’ve found that the plots that interest me the most are in the YA/teen fiction genre (ie the books I was reading in elementary/middle school) but the writing styles of these books feel a little too juvenile for me to REALLY enjoy them now. Idk if this makes much sense but I’m looking for books that have a more mature writing style targeted towards adults but the plot seems like it could be a Ya book.

Some of the books I enjoyed when I was younger include:
– Percy Jackson series
– 39 clues
– gone by Michael grant
– legend by Marie lu
– the testing by Joelle Charbonneau
– the keeper of the lost cities Shannon messenger
– the seven wonders series by Peter lerangis
– I am number four by pittacus lore