diff --git a/homeassistant/components/plex/button.py b/homeassistant/components/plex/button.py
index 58e0b78560b..985b4ccb4e9 100644
--- a/homeassistant/components/plex/button.py
+++ b/homeassistant/components/plex/button.py
@@ -38,17 +38,13 @@ class PlexScanClientsButton(ButtonEntity):
         self.server_id = server_id
         self._attr_name = f"Scan Clients ({server_name})"
         self._attr_unique_id = f"plex-scan_clients-{self.server_id}"
+        self._attr_device_info = DeviceInfo(
+            identifiers={(DOMAIN, server_id)},
+            manufacturer="Plex",
+        )
 
     async def async_press(self) -> None:
         """Press the button."""
         async_dispatcher_send(
             self.hass, PLEX_UPDATE_PLATFORMS_SIGNAL.format(self.server_id)
         )
-
-    @property
-    def device_info(self) -> DeviceInfo:
-        """Return a device description for device registry."""
-        return DeviceInfo(
-            identifiers={(DOMAIN, self.server_id)},
-            manufacturer="Plex",
-        )
diff --git a/homeassistant/components/plex/media_player.py b/homeassistant/components/plex/media_player.py
index 23f2895fd51..3e6875f98b9 100644
--- a/homeassistant/components/plex/media_player.py
+++ b/homeassistant/components/plex/media_player.py
@@ -117,6 +117,10 @@ def _async_add_entities(hass, registry, async_add_entities, server_id, new_entit
 class PlexMediaPlayer(MediaPlayerEntity):
     """Representation of a Plex device."""
 
+    _attr_available = False
+    _attr_should_poll = False
+    _attr_state = MediaPlayerState.IDLE
+
     def __init__(self, plex_server, device, player_source, session=None):
         """Initialize the Plex device."""
         self.plex_server = plex_server
@@ -136,9 +140,6 @@ class PlexMediaPlayer(MediaPlayerEntity):
         self._volume_level = 1  # since we can't retrieve remotely
         self._volume_muted = False  # since we can't retrieve remotely
 
-        self._attr_available = False
-        self._attr_should_poll = False
-        self._attr_state = MediaPlayerState.IDLE
         self._attr_unique_id = (
             f"{self.plex_server.machine_identifier}:{self.machine_identifier}"
         )
diff --git a/homeassistant/components/plex/sensor.py b/homeassistant/components/plex/sensor.py
index a705d11cb41..972cd8d4bc9 100644
--- a/homeassistant/components/plex/sensor.py
+++ b/homeassistant/components/plex/sensor.py
@@ -129,6 +129,11 @@ class PlexSensor(SensorEntity):
 class PlexLibrarySectionSensor(SensorEntity):
     """Representation of a Plex library section sensor."""
 
+    _attr_available = True
+    _attr_entity_registry_enabled_default = False
+    _attr_should_poll = False
+    _attr_native_unit_of_measurement = "Items"
+
     def __init__(self, hass, plex_server, plex_library_section):
         """Initialize the sensor."""
         self._server = plex_server
@@ -137,14 +142,10 @@ class PlexLibrarySectionSensor(SensorEntity):
         self.library_section = plex_library_section
         self.library_type = plex_library_section.type
 
-        self._attr_available = True
-        self._attr_entity_registry_enabled_default = False
         self._attr_extra_state_attributes = {}
         self._attr_icon = LIBRARY_ICON_LOOKUP.get(self.library_type, "mdi:plex")
         self._attr_name = f"{self.server_name} Library - {plex_library_section.title}"
-        self._attr_should_poll = False
         self._attr_unique_id = f"library-{self.server_id}-{plex_library_section.uuid}"
-        self._attr_native_unit_of_measurement = "Items"
 
     async def async_added_to_hass(self) -> None:
         """Run when about to be added to hass."""