Another idea so we can benefit from the codebase of "Universal Remote Card":
They support media platforms (like AndroidTV, ...).
Maybe it's possible to support sofabaton hub?
Here is the link: Universal Remote Card - Buttons, Touchpads, Sliders, and Keyboards for Multiple Platforms
And to readme of available platforms: GitHub - Nerwyn/universal-remote-card: A completely customizable universal remote card for Home Assistant. Supports multiple platforms out of the box. · GitHub
Sample android tv platform: universal-remote-card/src/models/maps/android_tv at main · Nerwyn/universal-remote-card · GitHub
P.S.: I am using the original sofabaton hacs hub integration and my hub has v8 firmware.
Trying your hub fork now.