From admin to standard user with Endpoint Privilege Management

Sorry, not fully understanding the question here and it's not really specific to this session either. However, are you referring to scripts already in production use that are unsigned? There is no way for the PowerShell execution policy to discriminate between when the scripts were put into production. The execution policy will apply to all scripts otherwise it's more or less useless, IOW, it's an all or nothing proposition otherwise it's meaningless. Is there reason you can't go back and sign your "venerable" scripts? This is the recommended path forward (along with setting the Execution Policy to All Signed and enabling constrained language mode.