- Risk it - they have no resources, so they probably won’t fight. But they might…
- Put one package with a queen into the lower brood box. Put a double layer of newspaper on top, then put the Flow super on top. Empty the second package into this (with no queen), put the inner cover and roof on and leave them for 3 days or so. When you come back, the bees should have chewed through the newspaper and combined with no fighting. You can then take the Flow super off and let them all build in one box. Sell the spare queen to your local bee club!
Personally, I would probably just risk it, but then I already have a couple of hives. Option 2 is safer if you don’t.
A third option would be to call the supplier and ask if you can cancel one package. They sell fast, so they may well be willing.
P.S. If you choose to combine both packages, and you have a spare queen, I would keep her in a cool location like a garage or basement, until I knew that the first queen had survived after the first 3 days. That way, you have a backup in case the package rejects the first one.