PathEnvVarsShellCompat.ps1

  # Resolve Paths that have environment variables that works for cmd, bash, and powershell
  # Resolve Paths with wildcards and splits on delimiters
class PathEnvVarsShellCompat {
  static [hashtable]$EnvVars = ({
    $hs = @{};
    Get-ChildItem -Path 'env:' | ForEach-Object { $hs.Add($_.Key, $_.Value) }
    $hs | Sort-Object;
  }.InvokeReturnAsIs());

  static [regex[]]$RGX_PathVars = @(
    [regex]::new('\%([A-Z_]+?)\%', [System.Text.RegularExpressions.RegexOptions]::IgnoreCase),     # Match Cmd Variables
    [regex]::new('\$env:([A-Z_]+?)\b', [System.Text.RegularExpressions.RegexOptions]::IgnoreCase), # Match PowerShell Variables
    [regex]::new('\$([A-Z_]+?)\b', [System.Text.RegularExpressions.RegexOptions]::IgnoreCase)      # Match Bash Variables
  );

  # Sub environment variables that works for cmd, bash, and powershell
  static [string] SubEnvVars([string]$aPath) {
    [hashtable]$Vars = [PathEnvVarsShellCompat]::EnvVars;
    foreach($rgx in [PathEnvVarsShellCompat]::RGX_PathVars) {
      foreach ($rMatch in $rgx.Matches($aPath)) {
        [string]$sKey = $rMatch.Groups[1].Value;
        [string]$sVal = $Vars.$sKey;
        if (!([string]::IsNullOrWhiteSpace($sVal))) {
          $aPath = $aPath.Replace($rMatch.Value, $sVal);
        } else {
          $sVal = [string](Get-Variable -Scope Script -Name $sKey -ErrorAction Ignore -ValueOnly)
          if (![string]::IsNullOrWhiteSpace($sVal)) {
            $aPath = $aPath.Replace($rMatch.Value, $sVal);
          }
        }
      }
    }
    return $aPath;
  }

  # Resolve Paths that have environment variables that works for cmd, bash, and powershell
  # Resolve Paths with wildcards and splits on delimiters
  static [System.Collections.Generic.List[string]] ResolveCompatPaths([string[]]$aPaths) {
    $result = [System.Collections.Generic.List[string]]::new();
    foreach ($path in $aPaths.Split([char[]]@(',', ';'), [System.StringSplitOptions]::RemoveEmptyEntries).Trim()) {
      [string]$subbed = [PathEnvVarsShellCompat]::SubEnvVars($path);
      foreach ($resolved in (Resolve-Path $subbed -)) { $result.Add($resolved.Path); }
    }
    return $result;
  }
}

# Resolve Paths that have environment variables that works for cmd, bash, and powershell
function Resolve-CPaths([parameter(Mandatory, ValueFromPipeline)][string[]]$paths) {
  [PathEnvVarsShellCompat]::ResolveCompatPaths($paths);
}





########################################
# Tests
########################################
$RoamPart = 'AppData\Roaming'
$AppCache = 'LocalLow\*\Win*\*Cache\..\..\**'

'%UserProfile%\$RoamPart' | Resolve-CPaths
# C:\Users\Derek\AppData\Roaming

 Resolve-CPaths('$UserProfile\$RoamPart\Code\**.json', 
               '$ENV:APPDATA\..\Roaming\Notepad++\stylers.xml',  
               '%LocalAPPDATA%\**\Crashpad\reports\*.dmp', 
               '%APPDATA%\..\$AppCache\**\*.json' 
               )
# C:\Users\Derek\AppData\Roaming\Code\languagepacks.json
# C:\Users\Derek\AppData\Roaming\Code\rapid_render.json
# C:\Users\Derek\AppData\Roaming\Code\storage.json
# C:\Users\Derek\AppData\Roaming\Notepad++\stylers.xml
# C:\Users\Derek\AppData\Local\Dropbox\Crashpad\reports\229cd2b4-7a08-4839-bae3-292e8ad4eb95.dmp
# C:\Users\Derek\AppData\Local\Dropbox\Crashpad\reports\22ab84a6-d133-4af5-86cf-c48f20c31543.dmp
# C:\Users\Derek\AppData\Local\Dropbox\Crashpad\reports\4c0fd893-8917-4353-adae-a77d66f7012b.dmp
# C:\Users\Derek\AppData\Local\Dropbox\Crashpad\reports\b5506a55-a06a-4b9f-810e-73f5dc79102c.dmp
# C:\Users\Derek\AppData\Local\Dropbox\Crashpad\reports\f60f26ca-6cac-4e9c-984f-42460c0db881.dmp
# C:\Users\Derek\AppData\LocalLow\Microsoft\F12\debugger\settings.json
# C:\Users\Derek\AppData\LocalLow\Microsoft\F12\emulation\settings.json
# C:\Users\Derek\AppData\LocalLow\Microsoft\F12\header\MyCode.json
# C:\Users\Derek\AppData\LocalLow\Microsoft\F12\network\settings.json