How about this idea:
basically, it adapt the behaviour of the Orion browser extension for macOS, and then if a text string is added, we have a shrunk-down version of the Orion browser, showing only the Kagi Translate webpage, sitting in the menu bar, and we just throw the text to that?
Personally, I'd like Orion to concentrate exclusively on macOS and not try to branch out. I don't want to relive an Electron disaster now, the way we did with DLL nightmares back in the day.