You can download V-Ray 4.2 for SketchUp 2021 from the official Chaos Group website:
The release of SketchUp 2021 marked a significant shift in the software's architecture, necessitating an update to its premier rendering engine. Chaos Group responded with , which was the first version to officially support SketchUp 2021. Users attempting to use older versions like 4.2 often find that the installers do not recognize the 2021 directory, or they experience frequent crashes. Official Download and Installation download vray 42 for sketchup 2021 link
While you asked for version , please note that V-Ray 5 was the primary version released specifically to support SketchUp 2021's new features. Current versions like V-Ray 7 also maintain backward compatibility with SketchUp 2021. Official Download Instructions You can download V-Ray 4
: Fully supports SketchUp 2017 through 2021 and beyond. Where to Download V-Ray for SketchUp Official Download and Installation While you asked for