Is multi-device consent the same as group-specific or cross-domain consent?

No

Multi-device consent concerns privacy choices that apply across multiple devices or end-user agents, such as a mobile device, tablet, or desktop browser.

Group-specific consent concerns privacy choices that apply across a defined group of websites, applications, services, or other digital properties.

If an implementation applies choices across both multiple devices and multiple digital properties, the notice should accurately explain both scopes.