How to prioritize one queue before a funnel

[#1]

I have 2 queues that go into a funnel and then to an InvokeHTTP processor. How can I make sure that there are no flowfiles in Q1 before taking flowfiles from Q2 to go into the funnel?

I've tried with priority attributes but this behavior doesn't seem to be what I'm looking for. Both Q's get read from and then after the funnel flowfiles from the high priority get processed first.

[#2]

@Tom De Backer

Did you tried using EnforceOrder processor in NiFi.

Then for first queue use increment 1 then for second queue use increment 2 so that flowfiles are going to funnel will always wait until the first queue flowfile came in.