Doylist:

Apparently the Klingon BoP was originally supposed to be a Romulan ship, but the script for The Search for Spock changed the villains to Klingons and they kept the ship. The classic green Klingon BoP has the feathers and raptor motif for that reason. Over the years they've added several Klingon ships under the same name, making it confusing.

Watsonian:

There's canonical support for technology exchanges between the Klingons and Romulans. The Enterprise Incident, for example. We know the Romulans used the D7 battlecruisers at some point, and I swear I remember reading that the Klingons bought some Romulan BoP, but I can't verify it rn.

Are they actually named those things by their builders, or are the names in English just what the federation calls them, sort of like how NATO has it's own names for a lot of cold war Soviet aircraft that aren't what the Soviets themselves called them?

I mean I know we can't see the entire universe, but how many crabships must there be?

2 wing flying has evolved uniquely multiple times. in thinking; bugs, birds...

its almost impossible for complex life (multi-celled organisms) to not exist on other planets somewhere considering we know it happened very successfully at least once. it would therefore make sense for 2-winged flight to be plausible in differing, non-contacted geophysical locations somewhere in the universe

Iirc, Klingon Birds-of-Prey originate from an earlier alliance with the Romulans prior to relations breaking down.

Would aquatic species name their ships after fish?

Romulans I feel actually just classify a ship their "war bird" as it moves through out their ships... "bird of prey" is different but may also be a clarification? Always wanted more romulan story...