This PS script uses Azure AZ module that outputs list of all Azure AD Apps along with their expiration date, display name, credentials (passwordcredentials or keycredentials), start date, key id. Useful to know the apps that are expiring and take action (renew).

Get-AzADAppsInfo.ps1

# Requires Azure AD PowerShell Module
#Prompts user to login using Azure Credentials
Connect-AzAccount

#Set the page size to your need.
$pgsize = 100;

$pg = 0;
$cnt = $null
$results = @()
do {
    
    $apps = Get-AzADApplication -First $pgsize -Skip ($pg*$pgsize)
    $cnt = $apps | Measure-Object
    if($cnt.Count -gt 0)
    {
        Write-Output "Page: $pg;  Found $($cnt.Count) apps"
        $apps | %{  
            $app = $_

            #$owner = Get-AzADApplicationOwner -ObjectId $_.ObjectID -Top 1
            $appCred = Get-AzADAppCredential -ObjectId $app.ObjectId

            $appCred | %{
                $results += [PSCustomObject] @{
                       
                    CredentialType = $_.Type;
                    DisplayName = $app.DisplayName; 
                    ExpiryDate = $_.EndDate;
                    StartDate = $_.StartDate;
                    KeyID = $_.KeyId;
                    AppId = $app.ApplicationId;
                    ObjectId = $app.ObjectId;
                    #Owners = $owner.UserPrincipalName;
                }  
            }
         }
    }
    $pg += 1;
} while ($cnt.Count -gt 0)
$results | FT -AutoSize 


# Optionally export to a CSV file
#$results | Export-Csv -Path "AppsInventory.csv" -NoTypeInformation 

This is a good article, which further corroborates my experience that Az PowerShell Module feels incomplete when working with Azure AD.
https://nedinthecloud.com/2019/07/16/demystifying-azure-ad-service-principals/