@Alvin Zhao - Even I was facing the same issue , how to print the actual value of the secret in Powershell as it showing *. In Powershell script, added the below but still its showing *** values for the secret.

$keyVaultValue = Get-AzKeyVaultSecret -VaultName "xxx" -Name "DBPass" - AsPlainText

Write-Host "Value of Value": $keyVaultValue

--Output

$keyVaultValue - ***

2. Also tried the below facing same issue showing ***

#$secret = (Get-AzKeyVaultSecret -VaultName "XXX" -Name "DBPass").SecretValueText