Can I "talk out loud"?
Does it have to be precise? If eg you wanted to display a time on an OLED in HH:MM format then I think the following might work: define 2 "multilevel switches" and one binary. Every 30 seconds toggle the binary switch, to trigger a scene on your controller. Then let that scene set the 2 dimmers to HH and MM.
That causes a bit of traffic, and it is not very precise, so an improved version would keep time on the Z-Uno and sync time eg every 10 minutes or so.
I have not used "multilevel" for time keeping, but I have used to select some "LED loop programs" on a Z-Uno (eg dim level 1 = rainbow, 2 = breathe, ...) and all controllers support this. It does not look "nice" on the controller but it works.