Finally found a way to do the install on Wine on Fedora — and that’s using Lutris. Lutris lets you install Windows games onto Linux and allows you to script the setup of the game environment to fit the game itself.
So I used it to download the WeChat binary, setup the environment (which involved downloading fonts via winetricks) and adding a registry hack. That seems to work now. Have added it to my app-installs playbook on Gitlab (https://gitlab.com/blenderfox/pixelbook-fedora-setup)
It’s not fully automated, it does still require you to run through the setup manually, and then quit both the WeChat application (so Lutris sees that the setup has exited) and Lutris before the playbook proceeds.