I have found a solution to my problem by accident, while on battery power. My MacBook told me that Energy Saver was using Significant Energy.
Short version: While running on Battery Power, open up System Preferences and go into Energy Saver. Disable “Automatic graphics switching.”
Long explanation: As soon as I unchecked the “Automatic graphics switching” box the screen’s color stopped changing and the sudden freezing has also stopped. Problem solved. Out of curiosity I enabled Automatic graphics switching and it then reverted back to the color shift and freezing.
This is the part I don’t understand. With Automatic graphics switching disabled, I plugged in my Power Adapter and the screen’s color still didn’t change. I then checked the box to enable Automatic graphics switching and the screen’s color also didn’t change back. When I was on battery power and enabled Automatic graphics switching the colors would change, while on power adapter the colors do not change. I unplugged my power adapter and the colors did not change no matter if the “Automatic graphics switching” box is enabled or disabled.
So this leads me to think that it has something to do with the Energy Saver function. I still have the “Automatic graphics switching” enabled to see if the color shift and freezing will return, but as of right now I am no longer having these issues.
MacBook Pro (Retina, 15-inch, Mid 2015)
macOS High Sierra Version 10.13.6
Processor 2.5 GHz Intel Core i7
Memory 16 GB 1600 MHz DDR3
Graphics Intel Iris Pro 1536 MB