SELECT 
  cscart_products_categories.product_id, 
  GROUP_CONCAT(
    IF(
      cscart_products_categories.link_type = "M", 
      CONCAT(
        cscart_products_categories.category_id, 
        "M"
      ), 
      cscart_products_categories.category_id
    )
  ) AS category_ids, 
  product_position_source.position AS position 
FROM 
  cscart_products_categories 
  INNER JOIN cscart_categories ON cscart_categories.category_id = cscart_products_categories.category_id 
  AND cscart_categories.storefront_id IN (0, 1) 
  AND (
    cscart_categories.usergroup_ids = '' 
    OR FIND_IN_SET(
      0, cscart_categories.usergroup_ids
    ) 
    OR FIND_IN_SET(
      1, cscart_categories.usergroup_ids
    )
  ) 
  AND cscart_categories.status IN ('A', 'H') 
  LEFT JOIN cscart_products_categories AS product_position_source ON cscart_products_categories.product_id = product_position_source.product_id 
  AND product_position_source.category_id = 7210 
WHERE 
  cscart_products_categories.product_id IN (
    99277, 99278, 99279, 99280, 99281, 99324, 
    99325, 99326, 99327, 99328, 99329, 
    99344, 99345, 99422, 99423, 99424, 
    99425, 99426, 99427, 99428, 99429, 
    99430, 99431, 99432, 99433, 99434, 
    99435, 99436, 99437, 99529, 99530, 
    99531, 99532, 99533, 99534, 99535, 
    99536, 99537, 99538, 99539, 99540, 
    99541, 99542, 99543, 99544, 99545, 
    99546, 99547
  ) 
GROUP BY 
  cscart_products_categories.product_id

Query time 0.00203

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "102.47"
    },
    "grouping_operation": {
      "using_filesort": false,
      "nested_loop": [
        {
          "table": {
            "table_name": "cscart_products_categories",
            "access_type": "range",
            "possible_keys": [
              "PRIMARY",
              "link_type",
              "pt"
            ],
            "key": "pt",
            "used_key_parts": [
              "product_id"
            ],
            "key_length": "3",
            "rows_examined_per_scan": 180,
            "rows_produced_per_join": 180,
            "filtered": "100.00",
            "using_index": true,
            "cost_info": {
              "read_cost": "18.33",
              "eval_cost": "18.00",
              "prefix_cost": "36.33",
              "data_read_per_join": "2K"
            },
            "used_columns": [
              "product_id",
              "category_id",
              "link_type"
            ],
            "attached_condition": "(`nuie_scalesta_net`.`cscart_products_categories`.`product_id` in (99277,99278,99279,99280,99281,99324,99325,99326,99327,99328,99329,99344,99345,99422,99423,99424,99425,99426,99427,99428,99429,99430,99431,99432,99433,99434,99435,99436,99437,99529,99530,99531,99532,99533,99534,99535,99536,99537,99538,99539,99540,99541,99542,99543,99544,99545,99546,99547))"
          }
        },
        {
          "table": {
            "table_name": "cscart_categories",
            "access_type": "eq_ref",
            "possible_keys": [
              "PRIMARY",
              "c_status",
              "p_category_id"
            ],
            "key": "PRIMARY",
            "used_key_parts": [
              "category_id"
            ],
            "key_length": "3",
            "ref": [
              "nuie_scalesta_net.cscart_products_categories.category_id"
            ],
            "rows_examined_per_scan": 1,
            "rows_produced_per_join": 9,
            "filtered": "5.00",
            "cost_info": {
              "read_cost": "45.00",
              "eval_cost": "0.90",
              "prefix_cost": "99.33",
              "data_read_per_join": "23K"
            },
            "used_columns": [
              "category_id",
              "usergroup_ids",
              "status",
              "storefront_id"
            ],
            "attached_condition": "((`nuie_scalesta_net`.`cscart_categories`.`storefront_id` in (0,1)) and ((`nuie_scalesta_net`.`cscart_categories`.`usergroup_ids` = '') or (0 <> find_in_set(0,`nuie_scalesta_net`.`cscart_categories`.`usergroup_ids`)) or (0 <> find_in_set(1,`nuie_scalesta_net`.`cscart_categories`.`usergroup_ids`))) and (`nuie_scalesta_net`.`cscart_categories`.`status` in ('A','H')))"
          }
        },
        {
          "table": {
            "table_name": "product_position_source",
            "access_type": "eq_ref",
            "possible_keys": [
              "PRIMARY",
              "pt"
            ],
            "key": "PRIMARY",
            "used_key_parts": [
              "category_id",
              "product_id"
            ],
            "key_length": "6",
            "ref": [
              "const",
              "nuie_scalesta_net.cscart_products_categories.product_id"
            ],
            "rows_examined_per_scan": 1,
            "rows_produced_per_join": 9,
            "filtered": "100.00",
            "cost_info": {
              "read_cost": "2.25",
              "eval_cost": "0.90",
              "prefix_cost": "102.48",
              "data_read_per_join": "144"
            },
            "used_columns": [
              "product_id",
              "category_id",
              "position"
            ]
          }
        }
      ]
    }
  }
}