using FluentNHibernate it is just adding this convention for tests only
public class NoForeignKeys : IReferenceConvention, IHasManyConvention
{
public void Apply(IManyToOneInstance instance)
{
instance.ForeignKey("none");
}
public void Apply(IOneToManyCollectionInstance instance)
{
instance.Key.ForeignKey("none");
}
}
using plain NHibernate you would need to iterate through all mapped classes properties and change it there.
foreach (var prop in config.ClassMappings.SelectMany(c => c.PropertyClosureIterator).Where(p => p.IsEntityRelation || <is hasmany>))
{
// set foreignkey name to "none"
}