Removing black lines in dragon quest monsters joker 3 professional

I am using a mac and my OS is 10.13, how do I remove the black lines like people do in pokemon games? The game runs between 40% and 70% outdoors and I have seen games running faster that way.

Hex editing the ROM if you’re familiar with it. Other than that, this is outside the scope of support and we can’t provide support with ROM hacks.