ExchangeOnline module - Could not load file or assembly

PSU uses version 4.46.0 of that assembly. I’m a bit surprised this mismatch would cause a problem.

    <PackageReference Include="Microsoft.Identity.Client" Version="4.46.0" />

Can you try to see what versions of assemblies are loaded in your dashboard? You can check with a function like this.

        function Show-UDAssemblies {
            Show-UDModal {
                $Assemblies = [AppDomain]::CurrentDomain.GetAssemblies() | Select-Object FullName | Sort-Object
                New-UDTable -Data $Assemblies