That's a great question.
The 192/Studio One 3 integration incorporates the UC Fat Channel, Pre amp and Z latency. So, with UC Ai running and Bypassed with Studio One 3 running, audio will pass thru Cue Mix output buses with the Studio 192 Template, or any user Template.
Interestingly, if you "quit" UC, the 192 will remember the last settings regarding Z latency, pres and Fat Channel. (only confirmed for Z, not for Fat channel function)
Cue Mixes and Template will not work if UC is running and ON (Mixer not Bypassed). UC has control. If you then Bypass the Mixer, Studio One will not reflect. You must then close Studio One 3 and re open. Or have UC not running, launch and open the Studio 192 Template, then run UC previously set to "Mixer Bypass". This will give control to the Studio One 3 for Cue Mix signal, Z latency and Fat Channel.
Mixer Bypass can be found on the setup page of the UC Ai control panel for the Studio 192 by clicking the blue cog wheel in the upper right corner of the mix window.