Speed up Out-File across multiple items - powershell

Question

I'm new to PowerShell but I'm trying to work through a folder of multiple files. I have files that will randomly be UTF-8, UTF-8 BOM, LE, BE, anything. I need all of them to be UTF-8 to be ingested by my ETL software our company uses. I tried numerous methods and the one below is the only one I got consistently working for any encoding.
This works almost instantly for one record, but when applying the foreach it takes roughly a minute and half for three items. I'm going to run this daily across thousands so this is unreasonable.
Any help would be appreciated.
'''
# Primary Variables
$Path = ".\Test\"
$Filename = "DriveThru_FileList.txt"
$Files = Get-ChildItem $Path\*.txt -Exclude ($Filename)
Foreach ($File in $Files){
$Content = Get-Content $File
$Content | Out-File -FilePath $File -Encoding "Default"
}
'''

Answer 1

I think you can speed this up by using .NET methods:
$Path = ".\Test\*"
$Filename = "DriveThru_FileList.txt"
# just store the files FullName in a string array
# when using te -Exclude switch, you must either also use -Recurse or
# have the path end in '\*' like in this example
$Files = Get-ChildItem -Path $Path -Filter '*.txt' -Exclude $Filename | Select-Object -ExpandProperty FullName
foreach ($file in $Files) {
# by default, this will create files in UTF-8 encoding without a Byte-Order Mark
# you can add a 3rd parameter if you need a different encoding like
# [System.IO.File]::WriteAllText($file, ([System.IO.File]::ReadAllText($file)), [System.Text.Encoding]::UTF8)
[System.IO.File]::WriteAllText($file, ([System.IO.File]::ReadAllText($file)))
}