When creating a new NiagaraSystem using existing system, the DefaultEffectType set in ProjectSettings is not reflected.

		// if the new system doesn't have a thumbnail image, check the thumbnail map of the original asset's upackage
		if(NewSystem->ThumbnailImage == nullptr)
		{
			FString ObjectFullName = SystemToCopy->GetFullName();
			FName ObjectName = FName(ObjectFullName);
			FString PackageFullName;
			ThumbnailTools::QueryPackageFileNameForObject(ObjectFullName, PackageFullName);
			FThumbnailMap ThumbnailMap;
			ThumbnailTools::ConditionallyLoadThumbnailsFromPackage(PackageFullName, {FName(ObjectFullName)}, ThumbnailMap);

			// there should always be a dummy thumbnail in here
			if(ThumbnailMap.Contains(ObjectName))
			{
				FObjectThumbnail Thumbnail = ThumbnailMap[ObjectName];
				// we only want to copy the thumbnail over if it's not a dummy
				if(Thumbnail.GetImageWidth() != 0 && Thumbnail.GetImageHeight() != 0)
				{
					ThumbnailTools::CacheThumbnail(NewSystem->GetFullName(), &Thumbnail, NewSystem->GetOutermost());
				}
			}
		}

		// modfier start
		{
			const UNiagaraSettings* NiagaraSettings = GetDefault<UNiagaraSettings>();
			check(NiagaraSettings);

			UNiagaraEffectType* RequiredEffectType = NiagaraSettings->GetRequiredEffectType();
			if (RequiredEffectType != nullptr)
			{
				NewSystem->SetEffectType(RequiredEffectType);
			}
			else
			{
				UNiagaraEffectType* DefaultEffectType = NiagaraSettings->GetDefaultEffectType();
				if (DefaultEffectType != nullptr)
				{
					NewSystem->SetEffectType(DefaultEffectType);
				}
			}
		}
		// modfier end