Packaging up and sending a bike from UK to Europe

I need to send my gravel bike (~11 kg) one way from the UK to Switzerland in a few weeks. As I am going by Eurostar part of the way, I was intending on using their Eurodespatch service, but this has been suspended indefinitely due to Covid-19.

Does anyone know of a cheap and reliable service for posting a bike from the UK to Switzerland?

Some couriers claim to post bikes but, when it comes to requesting a quick quote, they often just say that the parcel is too big or too heavy.

Also, any advice on how to dismantle and pack the bike up safely whilst saving space (will need to find a suitably small cardboard box) will be much appreciated.