After trying several methods to mount an ESP32 camera on a Prusa Mk4, I decided I wanted to connect the camera to the top of the Z-axis bracket. This cap sits over the right side and allows you to connect accessories via a GoPro style arm.
I printed this in PETG (0.2mm). PLA also worked, but the arms of the GoPro connector are more fragile. I used support material in between the leafs of the GoPro connector.
I used this with @MichalFanta's “Articulated Arm” to mount an ESP32 camera: https://www.printables.com/model/801345-articulated-arm
The author marked this model as their own original creation.