In my country, we sometimes call working arrangements where one company “leases” individual employees to another “body leasing”.
“Body” and “to lease” are obviously English words of good standing, but is the term itself used outside of Germany? When I google it, I get mostly German results (and the English ones might be from Germans writing in English).
Body leasing follows the long-standing trend in German business jargon to use English rather than German, even if the original doesn’t exist in the Anglosphere or has a different meaning. Think of Handy: where people actually speak English it’s usually a mobile.
English sounds “sexier”; Arbeitnehmerüberlassung sounds like one of those cumbersome compounds invariably — and opaquely — abbreviated in German law.
The common term among native speakers of English for this employment arrangement is outsourced (to a client/customer).
English, however, is an international language not owned exclusively by its native speakers. There is nothing odd about the German business community using such terms within its own language group. Problems only arise when native speakers have no idea what you’re talking about.