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 = 7309 
WHERE 
  cscart_products_categories.product_id IN (
    95946, 97574, 97575, 97682, 97683, 97684, 
    97685, 97686, 97687, 97688, 97689, 
    97690, 97691, 97692, 97693, 97694, 
    97695, 97696, 97707, 97708, 97709, 
    97710, 97711, 97712, 98054, 98055, 
    98056, 98057, 98058, 98059
  ) 
GROUP BY 
  cscart_products_categories.product_id

Query time 0.00184

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "68.40"
    },
    "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": 120,
            "rows_produced_per_join": 120,
            "filtered": "100.00",
            "using_index": true,
            "cost_info": {
              "read_cost": "12.30",
              "eval_cost": "12.00",
              "prefix_cost": "24.30",
              "data_read_per_join": "1K"
            },
            "used_columns": [
              "product_id",
              "category_id",
              "link_type"
            ],
            "attached_condition": "(`nuie_scalesta_net`.`cscart_products_categories`.`product_id` in (95946,97574,97575,97682,97683,97684,97685,97686,97687,97688,97689,97690,97691,97692,97693,97694,97695,97696,97707,97708,97709,97710,97711,97712,98054,98055,98056,98057,98058,98059))"
          }
        },
        {
          "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": 6,
            "filtered": "5.00",
            "cost_info": {
              "read_cost": "30.00",
              "eval_cost": "0.60",
              "prefix_cost": "66.30",
              "data_read_per_join": "15K"
            },
            "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": 6,
            "filtered": "100.00",
            "cost_info": {
              "read_cost": "1.50",
              "eval_cost": "0.60",
              "prefix_cost": "68.40",
              "data_read_per_join": "96"
            },
            "used_columns": [
              "product_id",
              "category_id",
              "position"
            ]
          }
        }
      ]
    }
  }
}

Result

product_id category_ids position
95946 7241,7309,7346,7208M 0
97574 7241,7309,7346,7208M 0
97575 7241,7309,7346,7208M 0
97682 7241,7309,7346,7208M 0
97683 7241,7309,7346,7208M 0
97684 7241,7309,7346,7208M 0
97685 7241,7309,7346,7208M 0
97686 7241,7309,7346,7208M 0
97687 7241,7309,7346,7208M 0
97688 7241,7309,7346,7208M 0
97689 7241,7309,7346,7208M 0
97690 7241,7309,7346,7208M 0
97691 7241,7309,7346,7208M 0
97692 7241,7309,7346,7208M 0
97693 7241,7309,7346,7208M 0
97694 7241,7309,7346,7208M 0
97695 7241,7309,7346,7208M 0
97696 7241,7309,7346,7208M 0
97707 7241,7309,7346,7208M 0
97708 7241,7309,7346,7208M 0
97709 7241,7309,7346,7208M 0
97710 7241,7309,7346,7208M 0
97711 7241,7309,7346,7208M 0
97712 7241,7309,7346,7208M 0
98054 7241,7309,7346,7208M 0
98055 7241,7309,7346,7208M 0
98056 7241,7309,7346,7208M 0
98057 7241,7309,7346,7208M 0
98058 7241,7309,7346,7208M 0
98059 7241,7309,7346,7208M 0