Intracompany transfer visas would be the appropriate temporary employment visa. To qualify, the company's employee must have worked for that company for some stipulated minimum period of time (varies by country), and must be a senior executive or highly trained technical specialist with unique & proprietary company information of their employer which cannot be obtained in the country of the company's other office.
Your Euro HR knowledge, experience would never be required in US office. If, say, a US client is opening a branch in Berlin, they want their HR consultant - or employment/staffing agency - to be a German in Berlin who knows good people in Berlin.
Consultants on a short-term assignment have some specialized expertise in the company's country before they would be sent temporarily to visit their foreign client's offices - typically business visa since it's very short term.
For major international consulting firms, international travel may be required, even extensive, for a certain echelon of expert. But they travel on business visas, a week in southern India, a couple days in Bangkok, a long layover in Vancouver airport, two days in NYC, and back to London or wherever their home base is. A great deal of their work is done remotely, especially for the actual consulting work. Business trips are maybe to visit the client or sign a contract, and they are OFF again, keeping airline seats filled.
been there, done that