Microsoft has changed the .NET Framework requirements of PowerShell module in Configuration Manager version 2103.
Configuration Manager 2103 and later versions require .NET Framework 4.7.2 or later.
Please update your .NET Framework to 4.7.2 or later, if you have Configuration Manager 2103 or later. CSM for SCCM is unable to import new applications to Configuration Manager if the requirements are not met.
You can download .NET Framework 4.7.2 Runtime installer from here: https://dotnet.microsoft.com/download/dotnet-framework/net472