[OVC] Fail with unsupported message when output argument is used for …

…pytorch (#27255)

### Details:
- *`output` argument cannot be used for pytorch as it is unclear what
behavior is expected in this case.*

### Tickets:
 - *#26457 *

---------

Co-authored-by: Roman Kazantsev <roman.kazantsev@intel.com>

tests/layer_tests/ovc_python_api_tests/test_pytorch.py

@@ -1181,6 +1181,19 @@ def forward(self, a, b):
         )}
 
 
+def create_pytorch_module_with_output(tmp_dir):
+    class PTModel(torch.nn.Module):
+        def forward(self, a, b):
+            return a + b
+
+    net = PTModel()
+    return net, None, {
+        "example_input": (
+            torch.tensor([5, 6], dtype=torch.float32),
+            torch.tensor([5, 6], dtype=torch.float32),
+        ), "output": "some_name"}
+
+
 class TestMoConvertPyTorch(CommonMOConvertTest):
     test_data = [
         'create_pytorch_nn_module_case1',
@@ -1255,6 +1268,23 @@ def test_mo_import_from_memory(self, create_model, ie_device, precision, ir_vers
         self._test_by_ref_graph(temp_dir, test_params,
                                 graph_ref, compare_tensor_names=False)
 
+    @pytest.mark.parametrize("create_model,exception", [
+        ('create_pytorch_module_with_output', AssertionError)
+    ])
+    @pytest.mark.nightly
+    @pytest.mark.precommit
+    def test_mo_import_from_memory_negative(self, create_model, exception,
+                                            ie_device, precision, ir_version,
+                                            temp_dir, use_legacy_frontend):
+        fw_model, graph_ref, mo_params = eval(create_model)(temp_dir)
+
+        test_params = {'input_model': fw_model}
+        if mo_params is not None:
+            test_params.update(mo_params)
+        with pytest.raises(exception):
+            self._test_by_ref_graph(temp_dir, test_params,
+                                    graph_ref, compare_tensor_names=False)
+
 
 def create_pt_model_with_custom_op():
     #

tools/ovc/openvino/tools/ovc/moc_frontend/pipeline.py

@@ -126,16 +126,13 @@ def merge_inputs(inputs, to_set_list):
                     res.append(p)
             return res
         iplaces = merge_inputs(model_inputs, iplaces)
-        # Currently this only work to reorder inputs/outputs
+        oplaces = []
+        # Currently this only work to reorder inputs
         to_override_all_inputs = check_places_are_same(model_inputs, [{"node": p} for p in iplaces])
         to_override_all_outputs = False
         if argv.output:
-            oplaces = []
             _outputs = fe_output_user_data_repack(input_model, argv.output, moc_front_end.get_name())
-            for out_desc in _outputs:
-                oplaces.append(out_desc["name"])
-            model_outputs = input_model.get_outputs()
-            to_override_all_outputs = check_places_are_same(model_outputs, [{"node": p} for p in oplaces])
+            assert len(_outputs) == 0, "`output` argument is not supported for PyTorch"
         if to_override_all_inputs and to_override_all_outputs:
             input_model.extract_subgraph(iplaces, oplaces)
         elif to_override_all_inputs: