I know what you mean, but it’s important to point out that you can’t super cancel a uoh, you have to link it, so the timing is definitely harder.
If you’re doing it as a meaty, you can just see it connect, hit confirm, and then super. It’s hard to describe the timing in text other than to say to make it touch the opponent just as he wakes up and just as the uoh is ending, it’s really something you need to just practice until you get. That said, this isn’t that effective because it’s really easy to see coming. Q’s uoh is pretty floaty so if you want to use it as a meaty you need to press the command a considerable time before the opponent actually wakes, and for most opponents that’s enough time to see and parry it.
The more effective way of linking uoh to super is by doing it at max range. I explain in this tread how to do this in a way that gets the computer to combo your super only if your uoh actually hit the opponent and not if your uoh gets blocked or parried. This is pretty useful, but again, some opponents can see your uoh coming because it’s so floaty and either block it or parry it.