Depends how strict you are about the definition.
CrossOver is Wine, which originally stood for Wine is Not an Emulator.
Open Source Software for running Windows applications on other operating systems.
www.winehq.org
Rosetta 2 is for all intents and purposes, an emulator, though some will argue just because its transpiled ahead of time rather than on-the-fly. But Rosetta ultimately allows x86 code to run on Apple Silicon. WINE allows you to run x86 Windows code on another x86 non-windows Platform.
So Rosetta is running CrossOver, and CrossOver is running the Windows APIs.