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 = 7223 
WHERE 
  cscart_products_categories.product_id IN (
    84564, 89049, 89050, 84649, 84650, 84345, 
    84346, 84327, 84328, 84517, 84518, 
    84583, 84584, 84648, 84644, 84516, 
    84582, 84512, 84578, 84626, 89039, 
    84299, 84300, 84319, 84320, 84494, 
    84560, 84314, 84668, 84669
  ) 
GROUP BY 
  cscart_products_categories.product_id

Query time 0.00130

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "19.00"
    },
    "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": 33,
            "rows_produced_per_join": 33,
            "filtered": "100.00",
            "using_index": true,
            "cost_info": {
              "read_cost": "3.57",
              "eval_cost": "3.30",
              "prefix_cost": "6.87",
              "data_read_per_join": "528"
            },
            "used_columns": [
              "product_id",
              "category_id",
              "link_type"
            ],
            "attached_condition": "(`nuie_scalesta_net`.`cscart_products_categories`.`product_id` in (84564,89049,89050,84649,84650,84345,84346,84327,84328,84517,84518,84583,84584,84648,84644,84516,84582,84512,84578,84626,89039,84299,84300,84319,84320,84494,84560,84314,84668,84669))"
          }
        },
        {
          "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": 1,
            "filtered": "5.00",
            "cost_info": {
              "read_cost": "8.25",
              "eval_cost": "0.17",
              "prefix_cost": "18.42",
              "data_read_per_join": "4K"
            },
            "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": 1,
            "filtered": "100.00",
            "cost_info": {
              "read_cost": "0.41",
              "eval_cost": "0.17",
              "prefix_cost": "19.00",
              "data_read_per_join": "26"
            },
            "used_columns": [
              "product_id",
              "category_id",
              "position"
            ]
          }
        }
      ]
    }
  }
}

Result

product_id category_ids position
84299 7223M 0
84300 7223M 0
84314 7223M 0
84319 7223M 0
84320 7223M 0
84327 7223M 0
84328 7223M 0
84345 7223M 0
84346 7223M 0
84494 7223M 0
84512 7223M 0
84516 7223M 0
84517 7223M 0
84518 7223M 0
84560 7223M 0
84564 7223M 0
84578 7223M 0
84582 7223M 0
84583 7223M 0
84584 7223M 0
84626 7223M 0
84644 7223M 0
84648 7223M 0
84649 7223M 0
84650 7223M 0
84668 7223M 0
84669 7223M 0
89039 7170,7223M 0
89049 7170,7223M 0
89050 7170,7223M 0