General "rules of thumb" for props -

If you want the MOST SPEED possible you run a 2 blade

Best all round "average" performance - 3 blade

Best "out of the hole", "lower rpm plaining" and "smoothest running" - 4 blade or 5 blade

Each boat/motor combo needs to be fitted with a prop that is best suited to how the owner or operator will use the boat.

An electric trolling motor was never designed to produce speed (as it's primary reason for existance), but if you use it to poke around on weedless flats a 3 blade prop would work well. However, if you are in a very weedy environment a 2 blade will catch less grass and tends to "self clear" a little easier - and when you want to go fast, hoist out the electric and fire up the gas outboard