They don’t, no. Obviously I asked that question of them right at the start.
No, the only (partial) solution was to buy esim cards from random small companies other than SwissCom that we had never heard of before, data only, and bite the bullet on roaming calls at high cost. This took a very long time to get to.
It would have been faster for someone who knows the Swisscom products to narrow the geography that their esim card can be bought from (ie German speaking countries and France and Italy only).