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 = 7300 
WHERE 
  cscart_products_categories.product_id IN (
    98264, 98265, 98274, 98275, 98276, 98277, 
    98278, 98279, 98280, 98281, 98282, 
    98283, 98284, 98285, 98286, 98287, 
    98288, 98289, 98290, 98291, 98292, 
    98293, 98294, 98295, 98296, 98297, 
    98298, 98299, 98300, 98301
  ) 
GROUP BY 
  cscart_products_categories.product_id

Query time 0.00163

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "39.87"
    },
    "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": 44,
            "rows_produced_per_join": 44,
            "filtered": "100.00",
            "using_index": true,
            "cost_info": {
              "read_cost": "4.68",
              "eval_cost": "4.40",
              "prefix_cost": "9.08",
              "data_read_per_join": "704"
            },
            "used_columns": [
              "product_id",
              "category_id",
              "link_type"
            ],
            "attached_condition": "(`nuie_scalesta_net`.`cscart_products_categories`.`product_id` in (98264,98265,98274,98275,98276,98277,98278,98279,98280,98281,98282,98283,98284,98285,98286,98287,98288,98289,98290,98291,98292,98293,98294,98295,98296,98297,98298,98299,98300,98301))"
          }
        },
        {
          "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": 44,
            "filtered": "100.00",
            "cost_info": {
              "read_cost": "11.00",
              "eval_cost": "4.40",
              "prefix_cost": "24.48",
              "data_read_per_join": "704"
            },
            "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": 2,
            "filtered": "5.00",
            "cost_info": {
              "read_cost": "11.00",
              "eval_cost": "0.22",
              "prefix_cost": "39.88",
              "data_read_per_join": "5K"
            },
            "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
98264 7301,7151M
98265 7301,7151M
98274 7302M
98275 7302M
98276 7302M
98277 7302M
98278 7302M
98279 7302M
98280 7302M
98281 7302M
98282 7302M
98283 7302M
98284 7302M
98285 7302M
98286 7302M
98287 7302M
98288 7302M
98289 7302M
98290 7303,7161M
98291 7303,7161M
98292 7303,7161M
98293 7303,7161M
98294 7303,7161M
98295 7303,7161M
98296 7303,7161M
98297 7303,7161M
98298 7303,7161M
98299 7303,7161M
98300 7303,7161M
98301 7303,7161M