Adding the button
Two fields belong together, and both are inside the product form. The hidden field names the target template, and the button triggers the switch.name attribute, not in the value. ~WS-AlternativeProductTemplate~ provides the field name under which the shop expects the template name.
The value contains the subshop as a directory, in the example deutsch/. With several subshops, the template therefore needs the matching path per subshop, otherwise the buyer ends up in the wrong language version.
The target template can be chosen freely. For a print view, a name such as ws_product_print.htm is a good choice, and for other purposes a different one accordingly.
