Mechanical disk and rim brakes are not appropriate for e-bikes. Even with high-quality pads that work decent in optimal conditions, the braking quality degrades quickly in rain, snow, or mud. Mechanical disk brakes don't have the appropriate stopping power you will need to compensate for the extra weight and higher speed you'll be traveling at on your e-Bike.
Brakes are the most important part of the eBike, you should invest in the best hydraulic breaks and rotors your budget can afford your safety is priceless plus you'll do less maintenance and they will be more reliable. You should be able to stop as hard and fast as you need to.