Hello,
Your question has a difficult answer that is not likely what you were expecting. The LSF0108 doesn't have an active output drive stage, so (in the traditional sense) it doesn't have an output impedance.
When the input device is driving low, the LSF0108 will act like a closed switch, with ron as specified in the datasheet.
To get the output impedance, the ron value is basically added to the impedance of whatever is driving the line low at the output.
When the input is driving the line high, the LSF0108 goes into a high impedance state. The output then has an impedance controlled by your choice of pull-up resistor. If you are using a 330 ohm resistor, for example, the output has a 330 ohm impedance.
Can you tell me more about your application? Perhaps I can be of assistance.
