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 = 166 
WHERE 
  cscart_products_categories.product_id IN (
    154, 53, 52, 228, 161, 165, 166, 86, 106, 
    105, 247, 101, 33, 32, 163, 244, 212, 
    155, 55, 69, 206, 184, 183, 133, 132, 
    125, 120, 223, 225, 224, 146, 147, 145, 
    117, 219, 222, 220, 221, 113, 157, 68, 
    29, 6, 8, 14, 9, 10, 19, 21, 50, 51, 49, 
    48, 54, 153, 164, 248, 65, 64, 63, 62, 
    66, 140, 141
  ) 
GROUP BY 
  cscart_products_categories.product_id

Query time 0.00069

JSON explain

{
  "query_block": {
    "select_id": 1,
    "read_sorted_file": {
      "filesort": {
        "sort_key": "cscart_products_categories.product_id",
        "table": {
          "table_name": "cscart_products_categories",
          "access_type": "ALL",
          "possible_keys": ["PRIMARY", "pt"],
          "rows": 267,
          "filtered": 28.08988762,
          "attached_condition": "cscart_products_categories.product_id in (154,53,52,228,161,165,166,86,106,105,247,101,33,32,163,244,212,155,55,69,206,184,183,133,132,125,120,223,225,224,146,147,145,117,219,222,220,221,113,157,68,29,6,8,14,9,10,19,21,50,51,49,48,54,153,164,248,65,64,63,62,66,140,141)"
        }
      }
    },
    "table": {
      "table_name": "cscart_categories",
      "access_type": "eq_ref",
      "possible_keys": ["PRIMARY", "c_status", "p_category_id"],
      "key": "PRIMARY",
      "key_length": "3",
      "used_key_parts": ["category_id"],
      "ref": ["c.cscart_products_categories.category_id"],
      "rows": 1,
      "filtered": 100,
      "attached_condition": "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')"
    },
    "table": {
      "table_name": "product_position_source",
      "access_type": "eq_ref",
      "possible_keys": ["PRIMARY", "pt"],
      "key": "PRIMARY",
      "key_length": "6",
      "used_key_parts": ["category_id", "product_id"],
      "ref": ["const", "c.cscart_products_categories.product_id"],
      "rows": 1,
      "filtered": 100
    }
  }
}