The Urufu-class does the same thing, but is a cruiser. "Expeditionary gunship" seems to be a phrasing that's meant to evoke the Plumeria-class, like Raz says, but make clear that unlike the original, this ship is meant to go off on its own and do the big booms. The Plumeria gets used that way because of Hanako, but it wasn't designed with that in mind. The Urufu can do that too, but it's designed for assisting with planetary operations.
I'd expect to see far fewer of these than the Urufu, as it appears less modular and has no civilian counterpart. However, if it's going to be a gunship, I'd call it a heavy one, as the Plumeria is considered "medium." Hell, drop "medium" or "heavy" altogether and just call the class "Nekovalkyrja expeditionary gunship". There's no question a vessel like this is unique to the Star Army of Yamatai; might as well classify it as such.