Export doesn't match timeline

No. To do any work in Premiere, you need to set up color management. Period.

We aren't in the golden days of yore anymore.  There are many different color spaces in normal professional use, and Premiere must be told what you want it to do with all that variance.

Completely rebuilt in the 25.x and forward builds for modern workflows.

I have used a (colour) filter with the Magic Bullet plugin. It's a filter I have always used and never had to set anything up for it in Premiere 2024. Are you saying that after putting on the filter, I need to actually do something in colour management too? Thanks!

Yup, no CM setup at all. Premiere can't work to what you want it to do if you don't tell it what you want to do.

I presume you're still exporting mostly Rec.709 ... and if so, for nearly all media you may use ...

• display color management on, plus extended dynamic range if on a Mac;
• auto detect log, and auto tonemapping both on;
• for most users, working color space of Rec.709;
• sequence color space matching the working space of Rec.709;
• use ONLY export presets that do not have HLG or PQ in the preset names.

You don't show your color management settings. The export settings are useless for CM issues. Or there may be a media or GPU issue, but ... first ... we need to see your color management settings.

Color workspace, Lumetri Panel, SETTINGS tab... the one named Settings.

A screen grab or two of the entire thing, with all sections twirled open.

See her4e, before on timeline and after export. See also settings.

As noted, that's because you are not setting your color management controls within Premiere to what you need. The CM tools are far more extensive now than before, due to the varying color spaces and dynamic range of modern media and workflow needs. 

Premiere's CM is nearly as expansive as Resolve now, in many ways. IF you pay attention to it, of course. But you need to go to their help files on their CM stuff.

At a minimum, display color management, auto detect log, and auto tonemapping should be on unless you are a totally advanced worker and know what CM setting you need differently.

Working in Rec.709 sequence color space is still advisable, as HDR spaces are the Wild Wild West yet.

Then of course there is the separate issue. Which only occurs on Macs without Reference modes. Where those specific Macs use a wrong display gamma, essentially gamma 1.96, rather than the specified Rec.709 standard of gamma 2.4.

So the image is notably brighter in the shadows, and the colors are not properly mapped to the Retina monitor's P3 color space, appearing a bit faded, with the white point a bit off. This will be seen only in QuickTime Player, Chrome, and Safari browsers.

On the Macs without Reference modes, using VLC, Potplayer, and Firefox browser, will typically show a more correct Rec.709  image on those computer screens.