2011 MacBookPro 15" + HighSierra 10.13.6 + DisplayLink 4.3.1:Rotate External Monitor?
 

My internal GPU & Thunderbolt adapter gave up the ghost, so I bought a USB DisplayLink adapter to try to run my external monitor. After some fiddling, I got it going in "Separate Desktops" mode, but...

I can't get the secondary display to rotate into portrait mode. The FAQ method of enabling the "Rotate" menu option works, but only for the laptop display. And when I rotate the laptop display, the secondary monitor also rotates, but in the opposite direction (?) . It's hard to figure out exactly what's going on, plus after the display rotates, the mouse is really hard to use. :(

Is there a way to get "Rotate" to work only on the external / DisplayLink monitor?

Thanks!

same question over here!

It is not supported in that macOS version.
https://support.displaylink.com/know...0-13-4-10-13-6

Please update to Mojave or Catalina.