>>96053967It wouldn't quite work with either of them.
Sororitas are, ultimately, going to be straight maid art with a bit of 40k chrome daubed on top. They're still women, after all. Even if they're shown as pissed off about it, it's not like tsundere/reluctant/resentful maid art/characters have never been done before.
AdMech: maybe a bit more you can play with here, but you're effectively going to be recycling the Robot Butler tropes. Perhaps more reliant on wordplay for potential humour rather than art.
The marines, though, are the old "big burly man in cute frilly outfit" juxtaposed absurdity. You get the joke at a glance, similar to the related one I've seen somewhere of the Imperial Knight Maid Cafe.
A full codex though? Really, it's another example of a quick, one-panel "mild smile" joke being stretched beyond its limits and ran so far into the ground it's probably spelunking at this point.