I have an issue doing the screen scroll trick I'm playing in the nestopia emulator with the USA (PRG1) rom. I am able to do the trick on the left side of the screen but when I try to do it on the right side doesn't go through.

You're most likely on the wrong pixel. Use this diagram to help align Link in the right spot.

Are you swinging your sword to help buffer the input, maybe? If I remember correctly, that works on the left side of the screen, but not on the right side (because you can't use your sword too close to that edge of the screen). Screen-scrolling on the right does require a one-frame dpad tap, without using the sword.

(Personally, I'm pretty okay with scrolling on the right, but I still have a hard time getting sword-buffering on the left to work properly for some reason.)

Here is a video from EunosXX that I found helpful