Max Shutter speed
Leica CL can shoot continuously at max speed of
10.0 fps and has max shutter speed of
1/8000 sec. CL also has an electronic shutter which can shoot silently at max speed of
1/25000s. One thing to keep in mind is that electronic shutter may cause rolling shutter / jello effects, and also banding issues under artificial light on your images.
Flash
Unfortunately CL doesn't have a built-in flash but it has a flash shoe for mounting external flashes.
Focusing
Leica CL features a Contrast Detection autofocusing system. The AF system has 49 points to choose from. Leica CL also features
Face detection AF where it intelligently detects the faces in the frame and locks the focus automatically.