Same issue, "Internal error: missingPackageDescriptionModule". Tried removing / re-adding the package dependencies but xcode13.2 is stuck in the "Preparing to validate..." stage. issue on all projects (iOS and MacOS) on intel iMac & mbp M1max. both machines upgraded to Monterey 12.1.

FWIW, xcode 13.2 also started sending me those errors related to github.com certificate validation.