There is good information in Chuck’s post below. He linked that in response to questions about photos and videos. I think you can do this safely if have backups. There are so few questions about it, unless you’re going iPhotos > Plex, that it makes me think moving a photo library works well.
You asked about preserving tags. Did you mean to say metadata? Tags can mean several things in this context.
If this is treading on sacred storage, you might ping Chuck.
Would you consider tagging this photos-library too? That might help others later.
