Civilization has some wargame elements in it, but I was thinking more in line with hex-based wargames. Remember that old project of mine?
Still sitting on it and am hoping to revive it at some point
A conversion would likely be better as the game mechanics would already be established. The French magazine Jeux & Strategie had monthly (mostly) wargames published in it, with Ultimate Planet being taken from issue #2, and they are simple enough to allow for a reasonable conversion. Here's a link to the magazine archive if you understand French : https://www.abandonware-magazines.org/affiche_mag.php?mag=185&page=1