How many QHD displays can I connect to one side of the 13" MBP 4 TB 2016?
Check out Apples help as indicated below, but unofficially it looks like the Answer is two total external displays can be attached regardless of resolution or which side they are attached. Apple does not really mention QHD but its close enough to 4K, that you probably can't double it with the existing hardware.

Check your requirements

Check the ports on your Mac to find out whether you need an adapter.

Check how many displays your Mac supports: Choose Apple menu  &gt; About This Mac, click Support, then click Specifications. On the webpage that appears, the number of displays your Mac supports appears under Video Support.



Source Use external monitors with your Mac