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 = 7257 
WHERE 
  cscart_products_categories.product_id IN (
    97668, 97669, 97670, 97671, 97672, 97673, 
    97674, 97675, 97676, 97677, 97678, 
    97679, 97680, 97681, 97682, 97683, 
    97684, 97685, 97686, 97687, 97688, 
    97689, 97690, 97691, 97692, 97693, 
    97694, 97695, 97696, 97697
  ) 
GROUP BY 
  cscart_products_categories.product_id

Query time 0.01474

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "81.29"
    },
    "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": 90,
            "rows_produced_per_join": 90,
            "filtered": "100.00",
            "using_index": true,
            "cost_info": {
              "read_cost": "9.29",
              "eval_cost": "9.00",
              "prefix_cost": "18.29",
              "data_read_per_join": "1K"
            },
            "used_columns": [
              "product_id",
              "category_id",
              "link_type"
            ],
            "attached_condition": "(`nuie_scalesta_net`.`cscart_products_categories`.`product_id` in (97668,97669,97670,97671,97672,97673,97674,97675,97676,97677,97678,97679,97680,97681,97682,97683,97684,97685,97686,97687,97688,97689,97690,97691,97692,97693,97694,97695,97696,97697))"
          }
        },
        {
          "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": 90,
            "filtered": "100.00",
            "cost_info": {
              "read_cost": "22.50",
              "eval_cost": "9.00",
              "prefix_cost": "49.79",
              "data_read_per_join": "1K"
            },
            "used_columns": [
              "product_id",
              "category_id",
              "position"
            ]
          }
        },
        {
          "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": 4,
            "filtered": "5.00",
            "cost_info": {
              "read_cost": "22.50",
              "eval_cost": "0.45",
              "prefix_cost": "81.29",
              "data_read_per_join": "11K"
            },
            "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')))"
          }
        }
      ]
    }
  }
}

Result

product_id category_ids position
97668 7260M,7320
97669 7260M,7320
97670 7260M,7320
97671 7260M,7320
97672 7260M,7320
97673 7320,7260M
97674 7320,7260M
97675 7260M,7320
97676 7320,7260M
97677 7320,7260M
97678 7320,7260M
97679 7320,7260M
97680 7260M,7320
97681 7260M,7320
97682 7309,7241,7346,7208M
97683 7309,7346,7208M,7241
97684 7346,7208M,7309,7241
97685 7346,7208M,7309,7241
97686 7241,7208M,7309,7346
97687 7241,7309,7346,7208M
97688 7346,7208M,7309,7241
97689 7309,7241,7346,7208M
97690 7309,7241,7346,7208M
97691 7309,7346,7241,7208M
97692 7309,7241,7208M,7346
97693 7346,7208M,7309,7241
97694 7208M,7309,7346,7241
97695 7241,7346,7208M,7309
97696 7208M,7309,7241,7346
97697 7320,7260M