PowerShellGet 2.9.0 Preview Get-Module does not find AZ Module in PowerShell 5.1

[BohrenAn]

Prerequisites

• Write a descriptive title.
• Make sure you are able to repro it on the latest version
• Search the existing issues.

Steps to reproduce

Under PowerShell 5.1 i can't find the installed Module AZ (i think this behavior is not limited to the PowerShellGet 2.9.0 - that's also the same under PowerShellGet 2.2.5.

The AZ PowerShell Module is installed here C:\Program Files\WindowsPowerShell\Modules\Az\10.3.0

#PowerShell 5.1
Get-Module
Get-Module AZ -ListAvailable

#PowerShell 7
Get-Module
Get-Module AZ -ListAvailable

Expected behavior

Get-Module AZ -Listavailable returns the installed Module under PowerShell 5.1

Actual behavior

Get-Module AZ -Listavailable does not return the installed Module under PowerShell 5.1

Error details

no error is shown

Environment data

$PSVersionTable

Name                           Value
----                           -----
PSVersion                      5.1.22621.1778
PSEdition                      Desktop
PSCompatibleVersions           {1.0, 2.0, 3.0, 4.0...}
BuildVersion                   10.0.22621.1778
CLRVersion                     4.0.30319.42000
WSManStackVersion              3.0
PSRemotingProtocolVersion      2.3
SerializationVersion           1.1.0.1

and

$psversionTable

Name                           Value
----                           -----
PSVersion                      7.3.7
PSEdition                      Core
GitCommitId                    7.3.7
OS                             Microsoft Windows 10.0.22621
Platform                       Win32NT
PSCompatibleVersions           {1.0, 2.0, 3.0, 4.0…}
PSRemotingProtocolVersion      2.3
SerializationVersion           1.1.0.1
WSManStackVersion              3.0

Version

5.1 and 7.3.7

Visuals

No response