Adobe Premiere Pro - How to Import Stereo Audio From Sound Mix

Open your Premiere Pro Project and click on the Import Tab

Browse to the desired files

click checkbox to select multiple files

Choose Import at the bottom right

Duplicate your timeline

Select all the clips in the timeline and right click and 

choose Unlink

Select the audio files in the audio tracks

and delete them by pressing delete

Drag the stereo mix from the bin to the timeline on to audio track

Next delete empty audio tracks

>Sequence

>Delete Tracks

Choose All Empty Tracks

Click OK

Should only have the stereo track left in the timeline