What synth are you using? What version and build number of Sonar are you using?
Can you modulate the pan position in your synth - depending on your synth. Knowing your synth might help here.
You can also automate either the pan of the track or automate the pan parameter in the synth itself and use the draw square tool at 16th (set musical time snap to 1/8) and then move the automation nodes slightly to the left - as long as the hi-hat is the only note on the track.
You could also do it using Controller 10 on the track and use the PRV to put them in manually. Just put each CC10 event just before each hi-hat hit. Doing it this way you can create them as clips. Create one clip and then copy that clip.