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.company_id = 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 = 375 
WHERE 
  cscart_products_categories.product_id IN (
    427, 408, 382, 418, 1930, 381, 1529, 1465, 
    329, 439, 393, 394, 396, 383, 440, 327, 
    385, 405, 413, 1937, 414, 389, 426, 442
  ) 
GROUP BY 
  cscart_products_categories.product_id

Query time 0.00791

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "181.14"
    },
    "grouping_operation": {
      "using_temporary_table": true,
      "using_filesort": true,
      "cost_info": {
        "sort_cost": "19.42"
      },
      "nested_loop": [
        {
          "table": {
            "table_name": "cscart_categories",
            "access_type": "ALL",
            "possible_keys": [
              "PRIMARY",
              "c_status",
              "p_category_id"
            ],
            "rows_examined_per_scan": 115,
            "rows_produced_per_join": 2,
            "filtered": "2.00",
            "cost_info": {
              "read_cost": "27.56",
              "eval_cost": "0.46",
              "prefix_cost": "28.02",
              "data_read_per_join": "6K"
            },
            "used_columns": [
              "category_id",
              "company_id",
              "usergroup_ids",
              "status"
            ],
            "attached_condition": "((`eshopuga_upgr_4122`.`cscart_categories`.`company_id` = 1) and ((`eshopuga_upgr_4122`.`cscart_categories`.`usergroup_ids` = '') or find_in_set(0,`eshopuga_upgr_4122`.`cscart_categories`.`usergroup_ids`) or find_in_set(1,`eshopuga_upgr_4122`.`cscart_categories`.`usergroup_ids`)) and (`eshopuga_upgr_4122`.`cscart_categories`.`status` in ('A','H')))"
          }
        },
        {
          "table": {
            "table_name": "cscart_products_categories",
            "access_type": "ref",
            "possible_keys": [
              "PRIMARY",
              "pt"
            ],
            "key": "PRIMARY",
            "used_key_parts": [
              "category_id"
            ],
            "key_length": "3",
            "ref": [
              "eshopuga_upgr_4122.cscart_categories.category_id"
            ],
            "rows_examined_per_scan": 40,
            "rows_produced_per_join": 19,
            "filtered": "21.11",
            "index_condition": "(`eshopuga_upgr_4122`.`cscart_products_categories`.`product_id` in (427,408,382,418,1930,381,1529,1465,329,439,393,394,396,383,440,327,385,405,413,1937,414,389,426,442))",
            "cost_info": {
              "read_cost": "92.00",
              "eval_cost": "3.88",
              "prefix_cost": "138.42",
              "data_read_per_join": "310"
            },
            "used_columns": [
              "product_id",
              "category_id",
              "link_type"
            ]
          }
        },
        {
          "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",
              "eshopuga_upgr_4122.cscart_products_categories.product_id"
            ],
            "rows_examined_per_scan": 1,
            "rows_produced_per_join": 19,
            "filtered": "100.00",
            "cost_info": {
              "read_cost": "19.42",
              "eval_cost": "3.88",
              "prefix_cost": "161.73",
              "data_read_per_join": "310"
            },
            "used_columns": [
              "product_id",
              "category_id",
              "position"
            ]
          }
        }
      ]
    }
  }
}

Result

product_id category_ids position
327 372,355,358,375,380,361,351,370,384,352,378,362,376,382,360,383,359,373,356,363,354,371,385,350,357,377,369,379,374,381,353,386,349M 0
329 353,349M,372,355,358,375,351,370,342,352,378,376,338,373,356,354,371,350,339,357,377,369,374 0
381 381,350,339,357,386,374,353,340,349,380,361,341,372,355,358,343,375,384,362,351,370,382,360,383,359,342,352,345,378,376,363,338,347,373,385,356,337M,354,371,344,379 0
382 354,377,371,344,369,379,381,350,339,357,386,374,353,340,349,341,372,355,358,343,375,384,351,370,382,383,342,352,345,378,376,338,347,373,385,356,337M 0
383 338,347,373,368,385,356,337M,354,377,371,344,381,350,339,357,386,361,374,353,340,349,341,372,362,355,358,360,343,359,375,384,351,370,363,342,352,345,378,376 0
385 342,352,345,378,376,338,347,373,368,356,369,388,337M,354,377,371,390,395,344,394,391,396,393,350,339,357,392,361,374,353,340,349,341,372,362,355,358,360,343,359,375,351,370,363 0
389 343,375,351,370,342,385,352,345,378,379,376,338,347,373,356,369,380,337M,381,354,377,371,344,386,350,339,357,374,353,340,382,383,384,349,341,372,355,358 0
393 383,384,349,341,372,355,358,343,375,351,370,342,385,352,345,378,379,376,338,347,373,356,369,380,337M,381,354,377,371,344,386,350,339,357,374,353,340,382 0
394 374,353,340,382,383,384,349,341,372,355,358,343,375,351,370,342,385,352,345,378,379,376,338,347,373,356,369,380,337M,381,354,377,371,344,386,350,339,357 0
396 371,344,350,339,357,374,353,340,349,341,372,355,358,343,375,351,370,342,352,345,378,376,338,347,373,356,369,337M,354,377 0
405 359,356,369,337M,363,354,377,371,344,350,339,357,368,374,353,340,388,349,390,395,341,372,355,358,394,391,396,343,375,393,392,351,370,361,342,352,345,378,376,362,338,347,360,373 0
408 352,345,378,386,376,338,347,373,356,369,337M,382,354,377,371,383,344,384,350,339,357,374,353,340,349,385,341,372,379,355,358,343,375,351,370,380,381,342 0
413 351,370,362,342,360,352,345,359,378,376,338,363,373,356,369,337M,354,377,371,344,368,350,339,357,374,353,340,349,341,372,355,358,361,343,375 0
414 341,372,355,358,361,343,375,351,370,362,342,360,352,345,359,378,376,338,363,373,356,369,337M,354,377,371,344,368,350,339,357,374,353,340,349 0
418 374,353,340,349,341,372,355,358,343,375,351,370,342,352,345,378,376,338,363,373,356,369,337M,354,377,371,344,350,339,357 0
426 350,339,357,381,374,386,353,340,349,341,372,355,358,343,375,382,383,384,351,370,342,352,345,378,376,338,373,356,385,337M,379,354,377,371,344 0
427 385,337M,379,380,354,377,371,344,350,339,357,381,347,374,386,353,340,349,341,372,355,358,343,375,382,383,384,351,370,342,352,345,378,369,376,338,373,356 0
439 338,373,385,337M,379,361,354,377,371,344,350,339,357,381,362,360,359,374,386,353,340,349,341,372,355,358,343,375,382,363,383,384,351,370,368,342,352,345,378,369,376 0
440 370,368,369,376,373,361,377,371,362,388,360,359M,374,390,395,394,391,396,372,393,392,375,363 0
442 375,363,378,370,368,380,369,376,385,379,373,361,377,371,381,386,362,360,359M,374,382,383,372,384 0
1465 392,382,342,383,352,345,356,372,384,338,375,363,378,370,368,337,380,354,344,369,347,376,385,379,373,350,339,357,353,340,361M,377,371,381,388,349,341,386,355,358,390,395,362,343,394,360,391,396,359,374,393,351 0
1529 390,395,362,343,394,360,391,396,359,374,393,351,392,342,352,345,356,372,384,338,375,363,378,370,368,337,380,354,344,369,347,376,385,379,373,350,339,357,353,340,361,377,371,381,388,349M,341,386,355,358 0
1930 361M,377,381,388,349,341,355,390,395,362,391,359,351,352,345,356,338,375,363,337,354,369,376,379,350,339,353,340 0
1937 350,339,371,386,353,340,358,361M,377,381,343,382,388,394,349,360,396,341,374,393,355,390,395,392,362,342,391,359,372,384,351,352,345,356,378,370,368,338,375,380,363,344,347,385,337,373,354,357,369,376,379 0