Monitoring 2 Mixers Simultaneously

[AiAlpha]

I have a Behringer Q502USB and a Behringer QX1222USB, is it possible to monitor both mixers simultaneously, if so how would I do it? If it helps the headset I'm currently using is an Audio-Technica BPHS1. If you need more info, I'm using the Q502USb' usb connection as my headphones mic interface for allowing my mic to work in games like csgo, and I'm using the QX1222USB to mix my in-game sound, music, and microphone to a single channel so I have more control over what my stream hears. The AT BPHS1' mic is getting split to both mixers.

 

[americanaudiophile]

If your connected the headphone out of each mixer to an additional mixer it would provide a monitor mix for your headphones.

 

[AiAlpha]

If your connected the headphone out of each mixer to an additional mixer it would provide a monitor mix for your headphones.

What mixer would you recommend? How much additional latency would this solution add? Will the monitor mix still be good for fps and other games that require decent directional audio?