Filling a gap in double-active free-swing double-doors
You could use two soft astragals and make them overlap slightly. 

If the sweep (soft part) is very thin, the misalignment of the closed doors will be almost unnoticeable.1 You'll have to shop around to see what you can get. A wider sweep is better because it will flex more. I think the "T" style is more attractive than the draft-stop style. You might have to add some wooden strips to the door edges to narrow the gap slightly. 

Here in cross section are some suggested arrangements:






Well, of course you will notice it because you know it is there. No one else will notice, trust me.