Yes, native interop works the same across all platforms (Linux, macOS, Windows, Android, iOS). You can just place a dynamic library with C linkage (.so, .dylib, or .dll file) into your app's folder, and then you can call the native functions as external functions in C#. For example, if your library exports the following C function:

    void printMessage(char *message) {
        printf("Message from C#: %s", message)
    }

You can call it from C# like this:

    MyLibrary.printMessage("Hello from C#!");

    public static class MyLibrary {
        [DllImport("MyLibraryName")]
        public static extern void printMessage(string message);
    }

C# takes care of marshalling data types, and an instance of a native object can be passed as an IntPtr. I'm currently developing web services for a new WebRTC-related product using .NET 5 on Ubuntu, and it's working well. One of the services utilizes a native C++ library and another utilizes a native Go-based library using the same approach. Java and Go are both good options, too.