OK, I pushed an alpha version here; BTHome Binding [4.0.0;4.9.0) . A lot of datatypes are not supported yet, but if there is any interest I’ll add more.
Unfortunately discovery doesn’t work as the BLE discovery mechanism in openHAB doesn’t forward advertisement service data. Reported here; [bluetooth] Provide serviceData as part of Bluetooth discovery data · Issue #16910 · openhab/openhab-addons · GitHub