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 = 7148 
WHERE 
  cscart_products_categories.product_id IN (
    94154, 94155, 94156, 94157, 94158, 94159, 
    94160, 94381, 94428, 94452, 94453, 
    94454, 94455, 94456, 94457, 94458, 
    94459, 94460, 94461, 94462, 94558, 
    94559, 94560, 94561, 94562, 94563, 
    94564, 94565, 94566, 94567
  ) 
GROUP BY 
  cscart_products_categories.product_id

Query time 0.00133

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "53.64"
    },
    "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": 94,
            "rows_produced_per_join": 94,
            "filtered": "100.00",
            "using_index": true,
            "cost_info": {
              "read_cost": "9.69",
              "eval_cost": "9.40",
              "prefix_cost": "19.09",
              "data_read_per_join": "1K"
            },
            "used_columns": [
              "product_id",
              "category_id",
              "link_type"
            ],
            "attached_condition": "(`nuie_scalesta_net`.`cscart_products_categories`.`product_id` in (94154,94155,94156,94157,94158,94159,94160,94381,94428,94452,94453,94454,94455,94456,94457,94458,94459,94460,94461,94462,94558,94559,94560,94561,94562,94563,94564,94565,94566,94567))"
          }
        },
        {
          "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": "23.50",
              "eval_cost": "0.47",
              "prefix_cost": "51.99",
              "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": "1.18",
              "eval_cost": "0.47",
              "prefix_cost": "53.64",
              "data_read_per_join": "75"
            },
            "used_columns": [
              "product_id",
              "category_id",
              "position"
            ]
          }
        }
      ]
    }
  }
}

Result

product_id category_ids position
94154 7194M
94155 7194M
94156 7194M
94157 7194M
94158 7194M
94159 7194M
94160 7194M
94381 7226,7225M
94428 7313,7338,7219M
94452 7341,7342,7343,7157M
94453 7341,7342,7343,7157M
94454 7341,7342,7343,7157M
94455 7341,7342,7343,7157M
94456 7341,7342,7343,7157M
94457 7265,7247M
94458 7341,7342,7343,7157M
94459 7341,7342,7343,7157M
94460 7341,7342,7343,7157M
94461 7341,7342,7343,7157M
94462 7341,7342,7343,7157M
94558 7241,7309,7346,7208M
94559 7241,7309,7346,7208M
94560 7241,7309,7346,7208M
94561 7241,7309,7346,7208M
94562 7241,7309,7346,7208M
94563 7241,7309,7346,7208M
94564 7241,7309,7346,7208M
94565 7241,7309,7346,7208M
94566 7241,7309,7346,7208M
94567 7241,7309,7346,7208M