I used to be a macOS user and had a “Keychron Q3 QMK Custom Mechanical Keyboard ISO Layout” keyboard. I was very satisfied with this keyboard. Now I have sold my Apple equipment and migrated to Linux.
Keychron currently cannot deliver keyboards with a Swiss German layout (all sold out). The Swiss German layout is very important to me. What alternative for Linux? It should be as close to 1:1 as possible to the Keychron.
Have you considered getting another ISO board and searching for ISO-CH keycaps? Keychron seems to have at least one set in stock, and if Digitec is a reputable store (I don’t know; dumb American here), they have some too.
Part of the reason why @wjrii suggests that is because ISO layout keyboards are uncommon in general and so searching for a particular one will limit your choices even further. And, of the DIY stuff to do, swapping keycaps isn’t too bad. If you really want to buy one with zero customization, you may be searching awhile.
AFAIK, ISO keyboards are just sending ANSI scan codes anyway – there’s two extra ones, KC_NUBS and KC_NUHS, for the keys ANSI lacks, but everything else is ANSI. The OS then does the remapping based on its settings for the language. E.g., in ISO-CH, this means that the Z key on the top row is actually sending the key code for KC_Y, but the OS is translating it to Z. Meanwhile, the Y on the bottom row is actually sending KC_Z and then getting translated to Y.
In poking around a little more, it appears Digitec is a pretty well known online retailer in Switzerland, and they seem to have some swiss boards in stock. Nothing super special, but I saw several Keychrons.
As others have mentioned, and you’re finding, ISO beyond UK or DE can be a challenge to find with pre-made keycaps. That really is the only difference though, and changing caps is not messy or risky. Even the Mac versus Linux difference only really lives in Software. Anything with a mature remapping utility should be able to be made to work.