SELECT 
  cscart_cp_blog_category_descriptions.*, 
  cscart_cp_blog_categories.*, 
  cscart_seo_names.name as seo_name, 
  cscart_seo_names.path as seo_path 
FROM 
  cscart_cp_blog_categories 
  LEFT JOIN cscart_cp_blog_category_descriptions ON cscart_cp_blog_categories.category_id = cscart_cp_blog_category_descriptions.category_id 
  AND cscart_cp_blog_category_descriptions.lang_code = 'ru' 
  LEFT JOIN cscart_seo_names ON cscart_seo_names.object_id = cscart_cp_blog_categories.category_id 
  AND cscart_seo_names.type = 'u' 
  AND cscart_seo_names.dispatch = '' 
  AND cscart_seo_names.lang_code = 'ru' 
  AND cscart_seo_names.company_id = cscart_cp_blog_categories.company_id 
WHERE 
  cscart_cp_blog_categories.category_id = 1 
  AND cscart_cp_blog_categories.company_id = 1

Query time 0.00070

JSON explain

{
  "query_block": {
    "select_id": 1,
    "const_condition": "1",
    "table": {
      "table_name": "cscart_cp_blog_categories",
      "access_type": "const",
      "possible_keys": ["PRIMARY"],
      "key": "PRIMARY",
      "key_length": "3",
      "used_key_parts": ["category_id"],
      "ref": ["const"],
      "rows": 1,
      "filtered": 100
    },
    "table": {
      "table_name": "cscart_cp_blog_category_descriptions",
      "access_type": "const",
      "possible_keys": ["PRIMARY"],
      "key": "PRIMARY",
      "key_length": "9",
      "used_key_parts": ["category_id", "lang_code"],
      "ref": ["const", "const"],
      "rows": 1,
      "filtered": 100
    },
    "table": {
      "table_name": "cscart_seo_names",
      "access_type": "const",
      "possible_keys": ["PRIMARY", "dispatch"],
      "key": "PRIMARY",
      "key_length": "210",
      "used_key_parts": [
        "object_id",
        "type",
        "dispatch",
        "lang_code",
        "company_id"
      ],
      "ref": ["const", "const", "const", "const", "const"],
      "rows": 1,
      "filtered": 100
    }
  }
}