That is so interesting - the medieval period is my favourite time in history. I'd love to hear more about these ships.
The largest seems to be 17 meters long (and there might be a couple more in the mud).
It'll certainly take some time until you can exactly say what kind of ships it had been - there aren't any example of Norwegian ships after the Vikings until then.
My guess is that they look similar to the caravels which were common in other countries in the late medieval period and afterwards. But: it can be hulks [holks] as well.