.NET核心web API，如何更改使用IAsyncEnumerable时返回的XML的根名称？

using Microsoft.AspNetCore.Mvc.Formatters;
using Microsoft.Net.Http.Headers;
using System.IO;
using System.Text;
using System.Threading.Tasks;
using System.Xml;

public class CustomXmlSerializerOutputFormatter : XmlSerializerOutputFormatter
{
    private readonly string _rootElementName;

    public CustomXmlSerializerOutputFormatter(string rootElementName)
    {
        _rootElementName = rootElementName;
        SupportedMediaTypes.Add(MediaTypeHeaderValue.Parse("application/xml"));
    }

    protected override XmlWriter CreateWriter(Stream writeStream, Encoding encoding)
    {
        var settings = new XmlWriterSettings
        {
            OmitXmlDeclaration = true,
            Indent = true
        };

        var writer = XmlWriter.Create(writeStream, settings);
        writer.WriteStartElement(_rootElementName); // 修改根元素名称
        return writer;
    }
}

services.AddControllers(options =>
{
    options.OutputFormatters.RemoveType<XmlSerializerOutputFormatter>();
    options.OutputFormatters.Add(new CustomXmlSerializerOutputFormatter("NewRootElementName")); // 设置新的根元素名称
});