16x19 will play completely different than 18x20, no matter the string setup.
You can try to get close, but finding an identical feel will not happen.
Let's not forget that different racquet brands will play different too. Wilson, Babolat, Head, Volkl, Donnay, Dunlop, etc all play differently, even the ones with identical specs.
Bullfan, "Bull rap, there is video evidence." and "Dude it's on the Internet, and hasn't been hidden."