In xpath/xquery builder in oxygen:
set xquery 3.0
declare default element namespace "http://www.tei-c.org/ns/1.0";
let $names := for $n in //persName/string-join(descendant::*/text()," ") return $n
return string-join($names," ")
returns just the texts.
The equivalent in the xpath box above the editor
returns the strings, but also the system id etc for each that you then have to manually delete