If you want to use any of the smart features of the Eufy cameras then you will be streaming everything to the cloud even if you are not storing the data there. It is possible to use something like OpenCV to perform most of those smart tasks locally (even on something as simple as a raspberry pi) but I am not aware of any commercial cameras that do that.
I would love to find a camera that just streams to a local server (something like MotionEye) and have that provide the post processing for smart functionality. Most of the options I have found tend to involve making your own with a raspberry pi and camera. 