Ford computers only turn on the fuel pump for 2 seconds when key is turned on, it doesn't come on again until engine starts.
So you could be losing a bit of fuel pressure when engine sits.
To test if this is the reason:
Turn key on, count to 3, turn key off
Repeat 2 more times
Now try to start engine
If it fires right up then you are losing pressure, you will need to get/rent a fuel pressure gauge to try and ID where it might be leaking, but if you smell fuel it would be easier to find, lol.
If it still takes a few seconds to start then I would look at the spark system