P: Panorama stitching - mask out parts of images which should be used

It would be very helpful if there was option to mask out parts which should not be seen in the end result of the stitched panorama of Lightroom classic cc.

I want to keep the flexibility to stitch raws, but exlude parts of the picture to be seen in the end result.

If i would not care about raw I could use PS to do the job and mask out the parts by hand after the PS Pano stitching process.

In my case a needed puzzle of picture has a completely different building lightning. (Marina Bay and Sands Singapore) but I need the parts except the building which I do not have on other pictures.

Thanks in advance for o comment on that. I am sure so many people out there could need such a option.