Not with the UA Apollos, they provide a mixer with own effects.
There are low latency FX (calculated with the DSP’s) available.
The UA Apollos are not Direct Monitoring capable, since the mixer is always active.
So there is no usable switch for DM available with the Apollos.
Btw, the switch is on the page for the “Universal Audio Thunderbolt” settings.
If you want to print this hardware calculated FX (Amp simulations for example)
you should set the insert effects selector to UAD REC, otherwise it is set to UAD MON that indicates that, the send to the DAW is before the insert effects.
But I’m not sure about the UNISON preamps.
You can use the Console to do your monitoring.