Ah ok, the colours looked a little different, the Vespa crabo I see are a more orange/brown colour, whereas the one you have look quite dark, almost black at times. I didn't know if you had some different species over there that might look similar. I did check out the Asian Hornet (Vespa velutina) to compare the two species, but that looks very different.

I think yours might well be be Vespa crabo, and maybe the colour has changed as they are now dead?

This is one I found earlier in the year, she was alive, but one of her wings was damaged (maybe not emerging properly), so she was not very mobile, and so I could get very close to her

"During all of the summer we had 2, 3, 4 hornets in the kitchen everyday, that slipped in from the attic - had to rid of them by opening windows. Happily, nothing bad happened."

I think Hornets, along with all other wasps, are amazing creatures but I can understand they'd be annoying to deal with if they kept appearing inside your house like that. Fortunately I've not had to deal with anything more than the occasional single wasp flying in through a random open window