xrandr help - dual 4K and 1080p monitor setup, can't get scaling to work

Hey all, I can't seem to figure out how to use xrandr to get appropriate scaling for my monitors. I have a primary monitor that is horizontal, in front of me, and is 4K resolution. I have a vertical monitor to the left which is 1080p resolution. By default, everything is super big on the 1080p vertical monitor but things look great on the 4K monitor.

I have followed