I’m currently using MamyPoko AirFit (tape) for my 2-month old babygirl. Also weighing about 4-ish kg but she’s quite small size. No leakage so far, only when we forgot to change her diaper for too long; too much pee and it will leak a little to the back. Other than that, all is good for my LO as no diaper rash. Try getting a sample for size S before purchasing a whole pack, although it may take a while to reach you.
https://sg.mamypoko.com/en/news/sample-request.html