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 = 7192 
WHERE 
  cscart_products_categories.product_id IN (
    86510, 86665, 86734, 86786, 83056, 83605, 
    90892, 90971, 85106, 85107, 89824, 
    89876, 89948, 91514, 83059, 83608, 
    90895, 90974, 85322, 85419, 85470, 
    85521, 82635, 83532, 85065, 85151, 
    85197, 85243, 82838, 82839
  ) 
GROUP BY 
  cscart_products_categories.product_id

Query time 0.00136

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "17.29"
    },
    "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": 30,
            "rows_produced_per_join": 30,
            "filtered": "100.00",
            "using_index": true,
            "cost_info": {
              "read_cost": "3.27",
              "eval_cost": "3.00",
              "prefix_cost": "6.27",
              "data_read_per_join": "480"
            },
            "used_columns": [
              "product_id",
              "category_id",
              "link_type"
            ],
            "attached_condition": "(`nuie_scalesta_net`.`cscart_products_categories`.`product_id` in (86510,86665,86734,86786,83056,83605,90892,90971,85106,85107,89824,89876,89948,91514,83059,83608,90895,90974,85322,85419,85470,85521,82635,83532,85065,85151,85197,85243,82838,82839))"
          }
        },
        {
          "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": "7.50",
              "eval_cost": "0.15",
              "prefix_cost": "16.77",
              "data_read_per_join": "3K"
            },
            "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": "0.38",
              "eval_cost": "0.15",
              "prefix_cost": "17.30",
              "data_read_per_join": "24"
            },
            "used_columns": [
              "product_id",
              "category_id",
              "position"
            ]
          }
        }
      ]
    }
  }
}

Result

product_id category_ids position
82635 7192M 0
82838 7192M 0
82839 7192M 0
83056 7192M 0
83059 7192M 0
83532 7192M 0
83605 7192M 0
83608 7192M 0
85065 7192M 0
85106 7192M 0
85107 7192M 0
85151 7192M 0
85197 7192M 0
85243 7192M 0
85322 7192M 0
85419 7192M 0
85470 7192M 0
85521 7192M 0
86510 7192M 0
86665 7192M 0
86734 7192M 0
86786 7192M 0
89824 7192M 0
89876 7192M 0
89948 7192M 0
90892 7192M 0
90895 7192M 0
90971 7192M 0
90974 7192M 0
91514 7192M 0