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 = 7313 
WHERE 
  cscart_products_categories.product_id IN (
    86891, 91868, 92227, 92210, 85554, 85577, 
    85570, 85576, 85584, 85543, 85592, 
    92239, 85571, 85573, 85574, 91877, 
    91878, 91879, 91880, 91881, 91882, 
    91883, 85555, 85594
  ) 
GROUP BY 
  cscart_products_categories.product_id

Query time 0.00142

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "52.50"
    },
    "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": 92,
            "rows_produced_per_join": 92,
            "filtered": "100.00",
            "using_index": true,
            "cost_info": {
              "read_cost": "9.49",
              "eval_cost": "9.20",
              "prefix_cost": "18.69",
              "data_read_per_join": "1K"
            },
            "used_columns": [
              "product_id",
              "category_id",
              "link_type"
            ],
            "attached_condition": "(`nuie_scalesta_net`.`cscart_products_categories`.`product_id` in (86891,91868,92227,92210,85554,85577,85570,85576,85584,85543,85592,92239,85571,85573,85574,91877,91878,91879,91880,91881,91882,91883,85555,85594))"
          }
        },
        {
          "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": "23.00",
              "eval_cost": "0.46",
              "prefix_cost": "50.89",
              "data_read_per_join": "12K"
            },
            "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": 4,
            "filtered": "100.00",
            "cost_info": {
              "read_cost": "1.15",
              "eval_cost": "0.46",
              "prefix_cost": "52.50",
              "data_read_per_join": "73"
            },
            "used_columns": [
              "product_id",
              "category_id",
              "position"
            ]
          }
        }
      ]
    }
  }
}

Result

product_id category_ids position
85543 7313,7338,7219M 0
85554 7313,7338,7219M 0
85555 7341,7342,7343,7157M
85570 7313,7338,7219M 0
85571 7341,7342,7343,7157M
85573 7341,7342,7343,7157M
85574 7341,7342,7343,7157M
85576 7341,7342,7343,7157M
85577 7341,7342,7343,7157M
85584 7341,7342,7343,7157M
85592 7341,7342,7343,7157M
85594 7341,7342,7343,7157M
86891 7341,7342,7343,7157M
91868 7341,7342,7343,7157M
91877 7341,7342,7343,7157M
91878 7341,7342,7343,7157M
91879 7341,7342,7343,7157M
91880 7341,7342,7343,7157M
91881 7341,7342,7343,7157M
91882 7341,7342,7343,7157M
91883 7341,7342,7343,7157M
92210 7341,7342,7343,7157M
92227 7341,7342,7343,7157M
92239 7313,7338,7219M 0