opps, the 1st diagram i showed just an example on explaining how the 2 way switch working.
my situation is my house got this kind of 2 way switch but its controlling 2 lights at the same time. when u press one button, TWO light will on/off.

i want to modify it become pressing one button and one light will on/off.

my house original 2 way switch is one gang(one button only), so is it possible to modify become 2 gang?