Better to size the prop for 3s power and just fly slower on 2s than over size the prop for 3s and risk burning out the motor. I am assuming the recommended 2205 2300kV motor is used. A 2300kV motor with a 6x4 prop could easily pull over 20 amps on 3s.
Yes a 2204 2300kv motor is fine and can be used with the same props. The 22 is the dynamiter of the motor in millimeters and the 04 is the height of the motor stator in millimeters. The stator is the part the wires are wrapped around. So a 2204 motor is the same dynamiter and one millimeter shorter than a 2205. In general the larger the motor the more power it can use. However one millimeter is a small difference.