People view & Metadata

[This post contains formatting and embedded images that don't appear in email. View the post in your Web browser.]

As Rikk explained, you can filter the Keyword List for all keywords with the Person attribute. 

When you export a photo from LR with metadata, the Person attribute isn't preserved (there's no industry standard for preserving keyword attributes).  

"in the initial catalog these keywords (names) still have People-attribute but after adding them to my archive catalog, this information seems to be gone as well."

How are you moving the photos to the archive catalog?  If you do Export with the option Include: All Metadata (being sure to uncheck Remove Person Info), and then import into the archive catalog, the face rectangles, assigned face names,  and the person keywords (with the Person attribute) will all be preserved.

You can also use File > Export As Catalog and File > Import From Another Catalog, which preserves all the photo-specific metadata (and more, including stacks and collections).

---

One method for making person keywords easier to work with is to create a top-level keyword People and then tell LR to put all newly created person keywords (i.e. by People view) underneath People by right-clicking it and doing Put New Person Keywords Inside This Keyword:

When you export a photo with the Metadata option Write Keywords As Lightroom Hierarchy, the hierarchical keywords will be preserved in the field XMP:HierarchicalSubject.  While not an industry standard, some other non-Adobe apps know how to interpret that field.

"batch edit the metadata to fit certain requirements (that want me to put the name in specific place in the caption)."

You could use the Write Data Field plugin of the Bag-O-Goodies plugin to copy person keywords into the captions of a batch of photos. It has lots of options for customizing exactly how that copying is done.

"a way to find these names in specific unique metadata tag."

The face rectangles and the assigned names are stored in the XMP:RegionInfo structure in the XMP metadata. You can extract it using the free, authoritative Exiftool utility (which has a steep learning curve). XMP:RegionInfo is defined by the Metadata Working Group standard, developed by Adobe, Canon, Microsoft, Nokia (!), and Sony. Unfortunately, LR is the only app I know of that implements the standard and still exists.

"Instead of putting these names in [PersonShown] tag which would be intuitive and reusable"

Ideally, the face names would go both into Keywords and IPTC Person Shown In Image. I think more apps understand how to manipulate keywords than the IPTC "Extension" fields. In my workflow, I have some apps and popular web services that ignore IPTC Person Shown In Image.

Although not specifically what you are asking, does it help you to identify them if you set your Keyword List (Click on the small down arrow next to the magnifying glass) to People?