diff --git a/homeassistant/components/conversation/__init__.py b/homeassistant/components/conversation/__init__.py
index 5692ddf3a06..9b3d5ef8dff 100644
--- a/homeassistant/components/conversation/__init__.py
+++ b/homeassistant/components/conversation/__init__.py
@@ -266,15 +266,18 @@ async def websocket_list_agents(
 
     for agent_info in manager.async_get_agent_info():
         agent = await manager.async_get_agent(agent_info.id)
+
+        supported_languages = agent.supported_languages
+        if language and supported_languages != MATCH_ALL:
+            supported_languages = language_util.matches(
+                language, supported_languages, country
+            )
+
         agent_dict: dict[str, Any] = {
             "id": agent_info.id,
             "name": agent_info.name,
-            "supported_languages": agent.supported_languages,
+            "supported_languages": supported_languages,
         }
-        if language:
-            agent_dict["supported_languages"] = language_util.matches(
-                language, agent.supported_languages, country
-            )
         agents.append(agent_dict)
 
     connection.send_message(websocket_api.result_message(msg["id"], {"agents": agents}))
diff --git a/tests/components/conversation/__init__.py b/tests/components/conversation/__init__.py
index 7fb4468277b..6eadb068054 100644
--- a/tests/components/conversation/__init__.py
+++ b/tests/components/conversation/__init__.py
@@ -1,6 +1,8 @@
 """Tests for the conversation component."""
 from __future__ import annotations
 
+from typing import Literal
+
 from homeassistant.components import conversation
 from homeassistant.components.homeassistant.exposed_entities import (
     DATA_EXPOSED_ENTITIES,
@@ -12,11 +14,14 @@ from homeassistant.helpers import intent
 class MockAgent(conversation.AbstractConversationAgent):
     """Test Agent."""
 
-    def __init__(self, agent_id: str) -> None:
+    def __init__(
+        self, agent_id: str, supported_languages: list[str] | Literal["*"]
+    ) -> None:
         """Initialize the agent."""
         self.agent_id = agent_id
         self.calls = []
         self.response = "Test response"
+        self._supported_languages = supported_languages
 
     @property
     def attribution(self) -> conversation.Attribution | None:
@@ -26,7 +31,7 @@ class MockAgent(conversation.AbstractConversationAgent):
     @property
     def supported_languages(self) -> list[str]:
         """Return a list of supported languages."""
-        return ["smurfish"]
+        return self._supported_languages
 
     async def async_process(
         self, user_input: conversation.ConversationInput
diff --git a/tests/components/conversation/conftest.py b/tests/components/conversation/conftest.py
index 46f57dbcab9..85d5b5daa91 100644
--- a/tests/components/conversation/conftest.py
+++ b/tests/components/conversation/conftest.py
@@ -3,6 +3,7 @@
 import pytest
 
 from homeassistant.components import conversation
+from homeassistant.const import MATCH_ALL
 
 from . import MockAgent
 
@@ -14,6 +15,16 @@ def mock_agent(hass):
     """Mock agent."""
     entry = MockConfigEntry(entry_id="mock-entry")
     entry.add_to_hass(hass)
-    agent = MockAgent(entry.entry_id)
+    agent = MockAgent(entry.entry_id, ["smurfish"])
+    conversation.async_set_agent(hass, entry, agent)
+    return agent
+
+
+@pytest.fixture
+def mock_agent_support_all(hass):
+    """Mock agent that supports all languages."""
+    entry = MockConfigEntry(entry_id="mock-entry-support-all")
+    entry.add_to_hass(hass)
+    agent = MockAgent(entry.entry_id, MATCH_ALL)
     conversation.async_set_agent(hass, entry, agent)
     return agent
diff --git a/tests/components/conversation/snapshots/test_init.ambr b/tests/components/conversation/snapshots/test_init.ambr
index ac96f8947ff..017ee004a84 100644
--- a/tests/components/conversation/snapshots/test_init.ambr
+++ b/tests/components/conversation/snapshots/test_init.ambr
@@ -85,6 +85,11 @@
           'smurfish',
         ]),
       }),
+      dict({
+        'id': 'mock-entry-support-all',
+        'name': 'Mock Title',
+        'supported_languages': '*',
+      }),
     ]),
   })
 # ---
@@ -104,6 +109,11 @@
           'smurfish',
         ]),
       }),
+      dict({
+        'id': 'mock-entry-support-all',
+        'name': 'Mock Title',
+        'supported_languages': '*',
+      }),
     ]),
   })
 # ---
@@ -123,6 +133,11 @@
         'supported_languages': list([
         ]),
       }),
+      dict({
+        'id': 'mock-entry-support-all',
+        'name': 'Mock Title',
+        'supported_languages': '*',
+      }),
     ]),
   })
 # ---
@@ -142,6 +157,11 @@
         'supported_languages': list([
         ]),
       }),
+      dict({
+        'id': 'mock-entry-support-all',
+        'name': 'Mock Title',
+        'supported_languages': '*',
+      }),
     ]),
   })
 # ---
@@ -162,6 +182,11 @@
         'supported_languages': list([
         ]),
       }),
+      dict({
+        'id': 'mock-entry-support-all',
+        'name': 'Mock Title',
+        'supported_languages': '*',
+      }),
     ]),
   })
 # ---
@@ -182,6 +207,11 @@
         'supported_languages': list([
         ]),
       }),
+      dict({
+        'id': 'mock-entry-support-all',
+        'name': 'Mock Title',
+        'supported_languages': '*',
+      }),
     ]),
   })
 # ---
diff --git a/tests/components/conversation/test_init.py b/tests/components/conversation/test_init.py
index 8ab2f1748fe..4bcfcdbf3dc 100644
--- a/tests/components/conversation/test_init.py
+++ b/tests/components/conversation/test_init.py
@@ -1576,6 +1576,7 @@ async def test_get_agent_list(
     hass: HomeAssistant,
     init_components,
     mock_agent,
+    mock_agent_support_all,
     hass_ws_client: WebSocketGenerator,
     snapshot: SnapshotAssertion,
 ) -> None: