How can a 120 V 60 Hz incandescent bulb fixture work in a 230 V 50 Hz outlet?
The FIXTURE does not care what is the voltage or frequency. But if you put a 120V BULB in a fixture connected to 230V, the bulb will burn out from 2x over-voltage.
The question as stated is too simple and obvious. Perhaps we are all missing exactly what you are asking for?
Incandescent bulbs are basically just a wire heated to a point where it glows. So you could also just represent it as a resistor. Therefore, if you change the supply from 120V/60Hz to 230V/50Hz, the power output will be greater. Please note that frequency difference has no effect on a resistor. The lightbulb will work, but most likely only for a short period of time. The greater current will burn it out much, much faster.
Your question could also mean "How can I make a 120V/60Hz work with 230V/50Hz supply?" In that case, you would need to reduce the current flowing through the lightbulb. Simplest way is adding a resistor, more complex would be using PWM.