My mechanic remarked my car felt a little lumpy when warm after he gave it a once over last week (I’ve only had it for a few weeks and hadn’t really noticed). We did spot the PCV pipe was split (Part No: 7M0 128 101) and I’ve ordered a replacement but yet to receive and fit. This is our first line of investigation as the car is showing no fault codes. An air leak would give symptoms of rough running though so maybe you have something similar.
I find my car can be a little snatchy on the throttle – i.e when coming off or on of the throttle while cruising it doesn’t feel smooth but then at other times it’s fine. I don’t get exactly the same symptoms as yours but thought it was similar enough to post my experiences so far.