How to set which landscape mode is default (reverse landscape vs landscape)
Quoted from one of my previous answers:


  Use apps like Ultimate Rotation Control - with proper settings, it seamlessly integrates with system rotation toggle, and on top of that you can enable/disable any rotation direction, force apps that don't usually rotate to rotate, and set per-app rotation behavior.


Based on your description, set the first options to these values so you can click the app's notification to toggle rotation direction.



Do note that this is a paid app with a 7-day trial.