Reddit mentions of NORTHERN FURY: H-Hour

AFAIK there's unfortunately just no way to run the game with units from both databases at the same time, only one or the other. And even with third-world air forces, by 1980 pretty much all the WW2 era and even Korean War era planes were out of service, and most of the ships as well, or have long since been upgraded with much better equipment and sensors. So a direct simulation of 2019 equipment vs WW2 isn't possible in the game.

However, I think depending on the details of your scenario, you could do some simulations that would give you some ideas of what to expect. You could use prop engined trainers and light attack aircraft like the Super Tucano, Pucara, or OV-10 Bronco, or even some of the light jets like the BAe Hawk (especially if you manually control their speed) to get some idea of what the modern units would do against them. There are also at least a couple WW2 destroyers still kicking around (I found at least Gearing, Fletcher, and Sumner classes in the modern DB, although some have more modern radars and stuff) and might be some other ships as well.

And likewise in the Cold War DB there are a few units that might give you some data points to extrapolate from for the WW2 planes themselves vs modern units, like the F-15A, F-14A, and E-3A AWACS plane. You might also be able to get closer matches by looking at the RCS values given in the game to pick matching units from the databases to test sensor ranges, as I don't think the Cold War DB has any stealth units. For ships there's the Spruance class, original 688 Los Angeles class, and some others, which should all have radically better sensors and performance than the WW2 ships.

Of course, other media could be an inspiration if it hasn't already been, like Final Countdown, the Axis of Time trilogy, the World at War trilogy, and I'm sure several others.

Finally, I'll take this opportunity to post one of my favorite articles touching on this subject: Choreographing the Dance of the Vampires. And for another example of using CMANO to help write a book, there's now the (IMO) totally unique and yet decades after its time Northern Fury: H-Hour.