It's not supported. You are not able to generate an Xcode project from a MAUI iOS project.

Note: If you want to link the Objective-C static library into your MAUI project, you have to make a .net-ios binding project.

Please see Native Library Interop - .NET MAUI Community Toolkit - Community Toolkits for .NET | Microsoft Learn

Getting Started with Native Library Interop - Community Toolkits for .NET | Microsoft Learn

Creating Bindings for .NET MAUI with Native Library Interop - .NET Blog