https://github.com/gentlepumpkin/bi-aidetection
This one is for Blue Iris. Middleware is open-source however DeepStack is closed source. (It’s free to get an API key for now.)
Note: Deep stack is abandoned for a long time and I believe if the dev team ever come back, they will start charging for an API key because of this project 
Here is what I think about this setup;
-It will require a beefy processor to handle 2+ cameras. You will need to have a high-end i7 to run blue iris and this AI tool with DeepStack.
-Because everything is running on a CPU, I believe developers decided to only analyze motion alerts rather than analyzing the real-time stream. If blue iris misses a motion then the tool won’t help you.
-Limited AI functionality. (Who knows, maybe someone will adopt another engine into this tool in the future)
-High power consumption.