I get it 
So I won't be able to change the address in the setup() as it is called once.
I'll try to do it in the loop and I'm not optimistic neither because I suppose that the setup function is made for initializing the address and the event handlers so any changes in the loop() may not be considered.
I didn't gave up on the idea of simulating many sensors as this is my goal. I need to simulate many slave sensors using a shipset that communicates via I2C. Only arduino functions as an I2C slave.