Is your macOS system language set to something other than English?

If not, try it again (could be a problem on Microsoft's side).

If all else fails,, try the using the command line version of the utility. Detailed instructions can be found in the Unofficial Fusion Companion Guide https://communities.vmware.com/t5/VMware-Fusion-Documents/The-Unofficial-Fusion-13-for-Apple-Silicon...

Look for the topic in chapter 15: Windows 11 download tool in Fusion GUI fails to create ISO