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 = 7148 
WHERE 
  cscart_products_categories.product_id IN (
    99342, 99343, 99404, 99405, 99406, 99407, 
    99408, 99409, 99410, 99411, 99422, 
    99423, 99424, 99425, 99426, 99427, 
    99428, 99429, 99430, 99431, 99432, 
    99433, 99434, 99435, 99436, 99437, 
    99491, 99492, 99493, 99494, 99495, 
    99496, 99497, 99498, 99499, 99500, 
    99501, 99502, 99503, 99504, 99505, 
    99506, 99508, 99509, 99510, 99512, 
    99513, 99514, 99516, 99517, 99518, 
    99519, 99520, 99521, 99522, 99523, 
    99524, 99525, 99526, 99527, 99529, 
    99530, 99531, 99532, 99533, 99534, 
    99535, 99536, 99537, 99538, 99539, 
    99540, 99541, 99542, 99543, 99544, 
    99545, 99546, 99547, 99548, 99549, 
    99550, 99551, 99552, 99553, 99554, 
    99555, 99556, 99557, 99574, 99575, 
    99576, 100143, 100161, 100162, 100163
  ) 
GROUP BY 
  cscart_products_categories.product_id

Query time 0.00249

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "159.26"
    },
    "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": 280,
            "rows_produced_per_join": 280,
            "filtered": "100.00",
            "using_index": true,
            "cost_info": {
              "read_cost": "28.36",
              "eval_cost": "28.00",
              "prefix_cost": "56.36",
              "data_read_per_join": "4K"
            },
            "used_columns": [
              "product_id",
              "category_id",
              "link_type"
            ],
            "attached_condition": "(`nuie_scalesta_net`.`cscart_products_categories`.`product_id` in (99342,99343,99404,99405,99406,99407,99408,99409,99410,99411,99422,99423,99424,99425,99426,99427,99428,99429,99430,99431,99432,99433,99434,99435,99436,99437,99491,99492,99493,99494,99495,99496,99497,99498,99499,99500,99501,99502,99503,99504,99505,99506,99508,99509,99510,99512,99513,99514,99516,99517,99518,99519,99520,99521,99522,99523,99524,99525,99526,99527,99529,99530,99531,99532,99533,99534,99535,99536,99537,99538,99539,99540,99541,99542,99543,99544,99545,99546,99547,99548,99549,99550,99551,99552,99553,99554,99555,99556,99557,99574,99575,99576,100143,100161,100162,100163))"
          }
        },
        {
          "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": 14,
            "filtered": "5.00",
            "cost_info": {
              "read_cost": "70.00",
              "eval_cost": "1.40",
              "prefix_cost": "154.36",
              "data_read_per_join": "36K"
            },
            "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": 14,
            "filtered": "100.00",
            "cost_info": {
              "read_cost": "3.50",
              "eval_cost": "1.40",
              "prefix_cost": "159.26",
              "data_read_per_join": "224"
            },
            "used_columns": [
              "product_id",
              "category_id",
              "position"
            ]
          }
        }
      ]
    }
  }
}