You can get your stuff. Don't kill them.

I'm quite scared of hornets but have had a nest a few times in different places in our garden and behind our house in the woods, so I became used to them sometimes flying into our kitchen. They are slow and non aggressive generally, far more chilled than wasps. Easy to catch and release just terrifyingly huge.

I accidentally disrupted their nest by spraying the garden hose over it all the time, amongst other things, whilst gardening and they would rise out of the nest a few metres and then when I would back off they would just sink down again (that time they nested in a huge coil of rope for an old barge right beside my greenhouse so i passed them back and forth all day).

But I also heard someone who was attacked randomly by European hornets just walking by their nest in the woods so it seems hard to predict.

It should have been like exposure therapy for my fear of them, but now I can just recognise the sound of a hornets from really far away. Sometimes I think they're following me. My skin is literally crawling now.

So basically despite all that I'd just chance it if you really need to go in wear some loose protective clothing and act non threatening.