I missed Drampa when checking, but Dragalge's is clearly based ona sea dragon so it's dragon typing is more of a "pun" than anything else, and Eternatus is more of a winged serpent than a Chinese dragon.
And honestly, Drampa's weird enough to be an outlier. For one, it's a Normal Type with dragon as secondary so...
Drampa breaks my brain.
Like, aren't normal types supposed to be mundane animals?