diff --git a/powershell/llcsharp/operation/method.ts b/powershell/llcsharp/operation/method.ts
index 1efd7117ed6..a18586b58a3 100644
--- a/powershell/llcsharp/operation/method.ts
+++ b/powershell/llcsharp/operation/method.ts
@@ -396,20 +396,20 @@ export class NewOperationMethod extends Method {
 
     // replace any server params in the uri
     for (const pp of serverParams) {
-      url = url.replace(`{${pp.param.language.csharp?.name}}`, `"
+      url = url.replace(`{${pp.param.language.default.serializedName}}`, `"
         + ${pp.name}
         + "`);
     }
 
     for (const pp of pathParams) {
-      rx = rx.replace(`{${pp.param.language.csharp?.name}}`, `(?<${pp.param.language.csharp?.name}>[^/]+)`);
+      rx = rx.replace(`{${pp.param.language.default.serializedName}}`, `(?<${pp.param.language.default.serializedName}>[^/]+)`);
 
       if (this.viaIdentity) {
-        url = url.replace(`{${pp.param.language.csharp?.name}}`, `"
+        url = url.replace(`{${pp.param.language.default.serializedName}}`, `"
         + ${pp.name}
         + "`);
       } else {
-        url = url.replace(`{${pp.param.language.csharp?.name}}`, `"
+        url = url.replace(`{${pp.param.language.default.serializedName}}`, `"
         + ${newRemoveEncoding(pp, '', KnownMediaType.UriParameter)}
         + "`);
       }
@@ -435,7 +435,7 @@ export class NewOperationMethod extends Method {
         yield EOL;
         yield '// replace URI parameters with values from identity';
         for (const pp of pathParams) {
-          yield `var ${pp.name} = ${match.value}.Groups["${pp.param.language.csharp?.name}"].Value;`;
+          yield `var ${pp.name} = ${match.value}.Groups["${pp.param.language.default.serializedName}"].Value;`;
         }
       }
 
@@ -469,7 +469,7 @@ export class NewOperationMethod extends Method {
             // content length is set when the request body is set
             continue;
           }
-          yield hp.serializeToContainerMember(KnownMediaType.Header, new LocalVariable('request.Headers', dotnet.Var), hp.param.language.csharp?.serializedName || hp.param.language.default.serializedName, ClientRuntime.SerializationMode.None);
+          yield hp.serializeToContainerMember(KnownMediaType.Header, new LocalVariable('request.Headers', dotnet.Var), hp.param.language.default.serializedName, ClientRuntime.SerializationMode.None);
         }
         yield EOL;
       }
diff --git a/powershell/package.json b/powershell/package.json
index 308f6e460d6..1579cc13cf0 100644
--- a/powershell/package.json
+++ b/powershell/package.json
@@ -66,4 +66,4 @@
     "source-map-support": "0.5.13",
     "xmlbuilder": "10.1.1"
   }
-}
\ No newline at end of file
+}
diff --git a/powershell/plugins/cs-namer-v2.ts b/powershell/plugins/cs-namer-v2.ts
index 5e15783833b..260dc095464 100644
--- a/powershell/plugins/cs-namer-v2.ts
+++ b/powershell/plugins/cs-namer-v2.ts
@@ -140,6 +140,8 @@ function setSchemaNames(schemaGroups: Dictionary<Array<Schema>>, azure: boolean,
           namespace: '<INVALID_NAMESPACE>',
           fullname: '<INVALID_FULLNAME>'
         };
+        // xichen: for invalid namespace case, we won't create model class. So we do not need consider dup case
+        thisNamespace.delete(schemaName);
       }
 
       // name each property in this schema
diff --git a/powershell/plugins/llcsharp.ts b/powershell/plugins/llcsharp.ts
index 0d84bd25793..b4735cdffbf 100644
--- a/powershell/plugins/llcsharp.ts
+++ b/powershell/plugins/llcsharp.ts
@@ -12,21 +12,11 @@ import { Dictionary } from '@azure-tools/linq';
 
 const resources = `${__dirname}/../../resources`;
 
-function outerTest(service: Host, project: Project, fname: string, content: string) {
-  service.WriteFile(join(project.apifolder, fname), test(content, project.overrides), undefined, 'source-file-csharp');
-}
-
-function test(content: string, overrides: Dictionary<string>): string {
-  const a = applyOverrides(content, overrides);
-  return a;
-}
-
 export async function llcsharp(service: Host) {
   try {
     const project = await new Project(service).init();
 
-    await project.writeFiles(async (fname, content) => service.WriteFile(join(project.apifolder, fname), test(content, project.overrides), undefined, 'source-file-csharp'));
-    await project.writeFiles(async (fname, content) => outerTest(service, project, fname, content));
+    await project.writeFiles(async (fname, content) => service.WriteFile(join(project.apifolder, fname), applyOverrides(content, project.overrides), undefined, 'source-file-csharp'));
 
     // recursive copy resources
     await copyResources(join(resources, 'runtime', 'csharp', 'client'), async (fname, content) => service.WriteFile(join(project.runtimefolder, fname), content, undefined, 'source-file-csharp'), project.overrides);
diff --git a/tests-upgrade/Configuration.json b/tests-upgrade/Configuration.json
index 73ac6021127..2bf7cc7583e 100644
--- a/tests-upgrade/Configuration.json
+++ b/tests-upgrade/Configuration.json
@@ -32,7 +32,10 @@
     "extension-ms-discriminatorvalue",
     "extension-ms-examples",
     "extension-ms-longruningoperation",
-    "extension-ms-pageable"
+    "extension-ms-pageable",
+    "directive-aliasremoval",
+    "directive-cmdlet",
+    "directive-parameter"
   ],
   "BlackList": [
     "basic-get-querystr",