A good general workflow is: apply consistent global adjustments to the source frames first, then stitch, then do final finishing on the merged pano.

Why: matching white balance, exposure, contrast, and color across the individual frames helps the stitcher produce cleaner seams and a more consistent result. If your images were shot with the same settings, syncing those edits across all frames usually works well. Save output sharpening and final local adjustments until after the panorama is merged.

A caution: heavy pre-processing can sometimes reduce detail or make stitching harder, so keep the pre-stitch edits moderate and consistent. Also, if the final panorama would be extremely large for your computer to handle, pre-processing may be a practical necessity.

One important exception is when the frames don’t match well to begin with—for example, light changed during the sequence. In that case, correcting brightness differences before stitching can be necessary.

So, best practice: do basic, synchronized RAW/global corrections first; stitch; then refine seams, dodge/burn if needed, and finish with sharpening and any local edits on the final pano.