This is for going from a type 2 charging socket to the car right? Except for ones for older Leaf and a few other cars they’re all the same but some will be 16A (probably all your car takes), some 32A. Some also do 3-phase but they’re for the few cars that offer it. The combination of charger/car/cable determines the maximum charge rate so you won’t blow anything up using the wrong thing.
So if you’re looking secondhand it doesn’t matter too much, but for new there’s not a lot of difference in price so I’d get the higher capacity one because you’ll probably get a car later that will need it.