when i export all tracks as audio file mix, the balances have all changed,
It's not clear to me, what you want to achieve.
If you like to have one stereo file that sounds exactly like the project, then you have to bounce the project. Either by pressing Bnc on the Stereo Out Channel Strip or from the menu File > Bounce > Project or Section.
If you like to have separated, individual audio files to be exported, then go File > Export > All Tracks as Audio File or x tracks as audio file. Activate Include/Volume Pan Automation and set Normalize to Off. However, Plugins on your Stereo Out will here not be reflected as these are only individual tracks. If you like to have Aux and Bus Channel Strip to be exported as well, you have to create them by contol+click the icon on the corresponding channel strips in the mixer and selecting Create Tracks.