Windows Video exports look darker then Mac exports and in Premiere

@mauerfuchs_film 
I was having that same problem. I got the new Macbook Pro M1 14'' as my travel laptop, so I can get some work done when I'm not on my Windows desktop, and I've noticed a huge shift exporting the same project on Windows and Mac. The export from the Mac is definitely brighter.

Go to System Preferences > Displays > Presets and select HDTV Video (BT.709-BT.1886). 
That should fix it.

Color management. Whatever you expect ain't what's happening.

The Mac OS has a very unique way of partially applying Rec.709 to video files, and their Retina monitors are also different across different 'generations' of them. In fact, the Mac OS system has changed the way it handles video color management several times in recent years.

Windows ... may or may not sort of be applying correct color managment depending on what the user has selected in various options for the OS, the monitors, the GPU settings, and various app/player options. Yea, that's not helpful either.

Premiere is hard-coded to be run on systems abiding by all the Rec.709 broadcast standards:

• Video sRGB color primaries;
• Rec.709 profile;
• 2.4 gamma;
• 100 nits brightness for the monitor, and used in a semi-darkened room.

Follow that in setting up your system, and you'll be seeing pretty correct values. Slip up on any, you have no idea what you're seeing versus what would be seen on a correct system. And this is why many pro colorists spend more on calibration gear than most of us have between computer, monitors, and calibration gear.

That's after buying a Grade 1 Reference Monitor, a very special class of monitors different from standard computer monitors ... that tend to run above $4500USD for an HD screen of maybe 24" diagonal.

On a Mac/Retina, you need to use the "Display color management" option in the preferences. Premiere will look at your monitor's ICC profile, and attempt to mate the image to that screen and still end up with close to a proper image. You may or may not get better results with that setting on a PC.

Here's some resources.

Neil

“Why does my footage look darker”

How Display Color Management in Premiere Works

Color Management for Video Editors

Why Master on a Calibrated Display?

And my tutorial re: Premiere's color management from Mixinglight.com ... this is a freebie outside their paywall ... (also referenced by Jonny Elwyn's blog above)

Finishing at the Highest Possible Quality in Premiere Pro