Let's see...
Since Monsta X made me ask the question: current top is baby blue. My favorite Korean release is Gambler and I have, like, six favorite English songs, which baby blue is not any of them.
Fifty Fifty: is Cupid, and my favorites of theirs are OT5 songs. But it's not surprising the viral hit with nearly a billion streams hasn't been dethroned yet. Fun to see Pookie's made it to the top 5!
Baby DONT Cry: Bittersweet! It's tied with I Don't Care for my favorite titles, and Mama I'm Alright is my favorite B side, and that's at #5. But it's easy when an artist doesn't have a big discography, and I like everything they've released.

Kinda cheating.
i-dle: Currently it's Mono, which is solidly in the "it's fine" realm for me. I've lately been obsessed with Klaxon.
Yuqi: Currently some collab song called Fire, which has not lodged in my brain at all. I like Red Rover the most.
Minnie: Blind Eyes Red. Correct!! Finally!! Everyone correctly shares my taste for her, I better stop here.