What Transformer for Smart video Doorbell
OK, you need a transformer that delivers 16-24 volts and 30 VA. The 30 VA is equal to 30 watts. The first transformer you're looking at have windings that will give you three different voltages, depending on what voltage you need. None of the configurations deliver 30 watts or 30 VA. The second transformer gives one voltage, 16 Volts and 10 watts or 10 VA.  Keep looking for a transformer that will deliver what your specifications call for. the smart video systems require more power than the old hard wired ones.