Creating a Shortcut for Display Settings  

I am looking for a way to create a Keyboard Shortcut that switches my display setup for Windows 10



So essentially I am looking for a command/macro/shortcut/bat file that when it's run Screen A becomes the Primary Screen and Screen B becomes the Secondary screen, and an opposite command/macro/shortcut/bat file that when it's run Screen B becomes Primary and Screen A becomes the main

Do you know of a way to do this without installing additional programs?

The easiest way would be a command-line .bat shortcut with a key stroke assignment:
(lines 2 and 3 differ with your setup)

Code:

@echo off
cd "C:\Windows\System32\nircmd.exe"
nircmd.exe setprimarydisplay 1

... but, you gotta grab NirCmd, if you don't have it.