Hello!
I'm currently developing a twitch extension that allows viewers to mouse over cards while watching the stream.
This requires knowledge of what cards are on screen at any given time.
Suggestion
I think the best solution is to have the current game state saved to a file somewhere, this can then be read by another app.
There are a few other ways of doing this but each come with their own issues:
- Mod: requires a lot of setup, disables steam achievements
- Image recognition: issues with screenshot capture when in fullscreen + borderless, very inefficient, inaccurate especially with foil/holographic/polychrome