Heebiejeebies by Amine & Kehlani is the song, and the sound in question is found at 0:18, and continues for the majority of the song. How is this made and what effects are on it. Or is this a pure synth, if so which ?
As it says in the comments, there are several sounds. Based on this looping instrumental version, at 00:18, a synth or similar keyboard joins in, with drums (cymbals, kick drum, other drums). Some keyboard effects are also used.