Proof of concept for resetting a profile after editing. Profile changes only apply to the caller so cannot be within another function

Edit-Profile.ps1

New-Module -Name ProfileUtil -ScriptBlock {
    # This must live in a module. A module function runs in the module's
    # session state, leaving the caller's session state (and its current
    # scope) untouched, so the profile can be dot-sourced back into it.
    # As a plain function it would share the caller's session state and
    # the profile would load into the function's own scope instead.

    function Edit-Profile {
        [CmdletBinding()]
        param()

        $ErrorActionPreference = "Stop"

        $tmpProfile = $null
        try {
            $randomId = [Guid]::NewGuid().ToString('N')
            $profileDir = Split-Path -Parent $profile
            $fileName = Split-Path -Leaf $profile
            $tmpProfile = Join-Path $profileDir ".tmp.$randomId.$fileName"

            if (Test-Path -LiteralPath $profile) {
                Copy-Item -LiteralPath $profile -Destination $tmpProfile -Force
            }
            else {
                New-Item -ItemType File -Path $tmpProfile -Force | Out-Null
            }

            # Open the profile in the appropriate editor based on the platform
            # This should probably be improved to handle the various ways an
            # editor could be set or how it is run.
            if (-not $IsWindows) {
                & $env:EDITOR $tmpProfile
            }
            else {
                Start-Process -FilePath $tmpProfile -Verb Open -Wait
            }

            # We parse the temp profile to check for any syntax errors before
            # replacing the original profile.
            $err = @()
            $null = [System.Management.Automation.Language.Parser]::ParseFile(
                $tmpProfile,
                [ref]$null,
                [ref]$err)

            if ($err) {
                $pe = [System.Management.Automation.ParseException]::new($err)
                $eRecord = [System.Management.Automation.ErrorRecord]::new(
                    $pe,
                    "ScriptParseException",
                    [System.Management.Automation.ErrorCategory]::ParserError,
                    $null)
                $PSCmdlet.ThrowTerminatingError($eRecord)
            }

            # Once validated, replace the original profile with the temp profile
            Move-Item -LiteralPath $tmpProfile -Destination $profile -Force
            $tmpProfile = $null

            # Re-parse from the final location so the scriptblock's file info
            # ($PSScriptRoot, $PSCommandPath, error positions) points at
            # $profile, not the deleted temp file now that it is validated.
            $ast = [System.Management.Automation.Language.Parser]::ParseFile(
                $profile,
                [ref]$null,
                [ref]$null)

            # Get an unbound ScriptBlock from the Ast.
            $unboundSbk = $ast.GetScriptBlock()

            # PSModuleInfo is the only public way to bind a ScriptBlock to an
            # arbitrary session state. Create an empty one ($false) and point
            # it at the caller's SessionState.
            $shim = [psmoduleinfo]::new($false)
            $shim.SessionState = $PSCmdlet.SessionState

            # Bind the unbound ScriptBlock to the shim so it runs in the
            # context of the parent's session state
            $bound = $shim.NewBoundScriptBlock($unboundSbk)

            # Dot-source so it runs in the caller's *current* scope. Using &
            # would create a child scope and discard everything the profile
            # defines.
            $null = . $bound
        }
        finally {
            if ($tmpProfile) {
                Remove-Item -LiteralPath $tmpProfile -Force
            }
        }
    }
} | Import-Module