I have just wasted two hours chatting with Swiss con operators. I am now exhausted mid morning Monday. They didn't know that you cannot buy an eSIM from the UK.
The list of countries includes France, Italy, Switzerland and Germany but not the UK. I cannot get past this in the form they have given a phone number, but but it will cost more to court with no guarantee of success than the eSIM costs.
If anyone else has managed to purchase an eSIM with Swiss con from the UK, I would love to hear about it. But as far as I can tell it cannot be done and no operators could help me in setting it up. Nor were they willing to phone a number in the UK on callback in order to discuss and sort this out.
Since I am buying for my child, and the child will be with a group of 40 children it is impossible for that child to leave the group, go to a kiosk in the airport and get an eSIM there.
It has to be done remotely prior to the trip which is in two weeks time.
Thank you to everyone for trying to help, but Swiss con cannot seem to handle this simple and small request.