これを試して:
var results = Data.GroupBy(l => l.Name);
.SelectMany( g =>
new
{
Metadata = g.Key,
data = g
});
var pivoted = new List<PivotedEntity>();
foreach(var item in results)
{
pivoted.Add(
new PivotedEntity
{
Id = item.Id,
Model = item.data.Where(x => x.Name == "Model")
.FirstOrDefault().value,
Manufacturer = item.data.Where(x => x.Name == "Manufacturer")
.FirstOrDefault().value,
});
}
最初に新しいクラスを定義する必要があります。
public class PivotedEntity
{
public int Id {get; set;}
public string Model {get; set;}
public string Manufacturer {get; set;}
}