SELECT 
  a.attachment_id as 'attachment_id', 
  filename, 
  filesize, 
  category, 
  last_updated, 
  d.description as 'description' 
FROM 
  cscart_attachments as a 
  LEFT JOIN cscart_attachment_descriptions as d ON a.attachment_id = d.attachment_id 
WHERE 
  object_id = 61444 
  AND status = 'A' 
ORDER BY 
  d.description ASC

Query time 0.00284

JSON explain

{
  "query_block": {
    "select_id": 1,
    "filesort": {
      "sort_key": "d.description",
      "temporary_table": {
        "table": {
          "table_name": "a",
          "access_type": "ALL",
          "rows": 6837,
          "filtered": 100,
          "attached_condition": "a.object_id = 61444 and a.`status` = 'A'"
        },
        "table": {
          "table_name": "d",
          "access_type": "ref",
          "possible_keys": ["PRIMARY"],
          "key": "PRIMARY",
          "key_length": "3",
          "used_key_parts": ["attachment_id"],
          "ref": ["cscart_migrate.a.attachment_id"],
          "rows": 1,
          "filtered": 100
        }
      }
    }
  }
}

Result

attachment_id filename filesize category last_updated description
16037 SPS-0236_-_The_Alliance_3-Light_Chandelier_-_Rev_06.27.18.pdf 382428 1 1576857953 Alliance 3-Light Chandelier
16036 MKT-0025_-_Barn_Light_Electric_Finishes_-_REV_B.pdf 2418240 4 1605022423 Barn Light Electric Finishes
20725 MKT-0021_-_Optional_Accessories_-_REV_F.pdf 11539937 4 1681915822 Optional Accessories
16041 INS-0002_-_Stem_Mount_Pendant_-_Rev_V.pdf 133942 7 1576858127 Stem Mount Pendant Installation Instructions
16038 MKT-0014_-_Standard_Incandescent_Stem_and_Flush_Mount_Pendant_Specifications_-_REV_B.pdf 139985 4 1576858002 Stem Mount Pendant Specifications
16039 INS-0005_-_Stem_Mount_Pendant_Hang_Straight_Canopy_-_Rev_L.pdf 294531 7 1576858063 Stem Mount Pendant with Hang Straight Canopy
16040 INS-0006_-_Stem_Mount_Pendant_Heavy_Duty_Canopy_-_Rev_C.pdf 281460 7 1576858092 Stem Mount Pendant with Heavy Duty Canopy