SELECT 
  c.category_id, 
  cd.category, 
  COUNT(pc.product_id) AS products_count 
FROM 
  cscart_categories AS c 
  LEFT JOIN cscart_category_descriptions AS cd ON c.category_id = cd.category_id 
  LEFT JOIN cscart_products_categories AS pc ON c.category_id = pc.category_id 
  LEFT JOIN cscart_products AS p ON p.product_id = pc.product_id 
WHERE 
  p.company_id = 692 
  AND c.status = 'A' 
  AND p.status = 'A' 
GROUP BY 
  cd.category

Query time 0.02288

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "1985.84"
    },
    "grouping_operation": {
      "using_temporary_table": true,
      "using_filesort": false,
      "nested_loop": [
        {
          "table": {
            "table_name": "c",
            "access_type": "index",
            "possible_keys": [
              "PRIMARY",
              "p_category_id"
            ],
            "key": "c_status",
            "used_key_parts": [
              "usergroup_ids",
              "status",
              "parent_id"
            ],
            "key_length": "773",
            "rows_examined_per_scan": 406,
            "rows_produced_per_join": 40,
            "filtered": "10.00",
            "using_index": true,
            "cost_info": {
              "read_cost": "96.57",
              "eval_cost": "4.06",
              "prefix_cost": "100.63",
              "data_read_per_join": "442K"
            },
            "used_columns": [
              "category_id",
              "status"
            ],
            "attached_condition": "(`dev2`.`c`.`status` = 'A')"
          }
        },
        {
          "table": {
            "table_name": "cd",
            "access_type": "ref",
            "possible_keys": [
              "PRIMARY"
            ],
            "key": "PRIMARY",
            "used_key_parts": [
              "category_id"
            ],
            "key_length": "3",
            "ref": [
              "dev2.c.category_id"
            ],
            "rows_examined_per_scan": 1,
            "rows_produced_per_join": 40,
            "filtered": "100.00",
            "cost_info": {
              "read_cost": "10.15",
              "eval_cost": "4.06",
              "prefix_cost": "114.84",
              "data_read_per_join": "175K"
            },
            "used_columns": [
              "category_id",
              "lang_code",
              "category"
            ]
          }
        },
        {
          "table": {
            "table_name": "pc",
            "access_type": "ref",
            "possible_keys": [
              "PRIMARY",
              "pt",
              "idx_pc_product_id_type"
            ],
            "key": "PRIMARY",
            "used_key_parts": [
              "category_id"
            ],
            "key_length": "3",
            "ref": [
              "dev2.c.category_id"
            ],
            "rows_examined_per_scan": 101,
            "rows_produced_per_join": 4127,
            "filtered": "100.00",
            "using_index": true,
            "cost_info": {
              "read_cost": "13.48",
              "eval_cost": "412.78",
              "prefix_cost": "541.11",
              "data_read_per_join": "64K"
            },
            "used_columns": [
              "product_id",
              "category_id"
            ]
          }
        },
        {
          "table": {
            "table_name": "p",
            "access_type": "eq_ref",
            "possible_keys": [
              "PRIMARY",
              "status",
              "cscart_products_product_id_index",
              "idx_status"
            ],
            "key": "PRIMARY",
            "used_key_parts": [
              "product_id"
            ],
            "key_length": "3",
            "ref": [
              "dev2.pc.product_id"
            ],
            "rows_examined_per_scan": 1,
            "rows_produced_per_join": 298,
            "filtered": "7.22",
            "cost_info": {
              "read_cost": "1031.95",
              "eval_cost": "29.81",
              "prefix_cost": "1985.84",
              "data_read_per_join": "2M"
            },
            "used_columns": [
              "product_id",
              "status",
              "company_id"
            ],
            "attached_condition": "((`dev2`.`p`.`company_id` = 692) and (`dev2`.`p`.`status` = 'A'))"
          }
        }
      ]
    }
  }
}