No problem. Just assign one toon to Strafe Left and the other to Strafe Right. Whatever key you choose make sure it's the same one, so "G" on both if you like. When you hit that they will spread out.

Note that if you're auto-following with the secondary toon that he/she will be about 3 feet behind your main, so if you do that they'll be at 45 degree angles from each other. You can compensate by backpedaling on the main for a second before you hit the spread out key.

You'll see what I'm talking about.