How do you taunt?

Solution 1:

Taunting was not a mechanic that was explained in depth at any point, at least not until you start Route C/D and start controlling A2. Taunting as A2 is pretty straightforward, but apparently all characters can taunt.

According to the wiki, anyone can taunt by repeatedly flashing your flashlight in enemies' faces. The flashlight can be toggled on PS4 by pressing the L3 button and 2 on PC.

All characters can taunt by toggling the flashlight repeatedly with the enemy in the light's path.

Additionally, A2 can taunt enemies by holding down the light attack button (this is in lieu of an additional attack that 2B and 9S have). When A2 taunts this way, it affects a larger area than toggling the flashlight.