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 
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') 
WHERE 
  cscart_products_categories.product_id IN (
    159, 158, 245, 238, 239, 242, 243, 241, 
    240, 214, 217, 218, 207, 59, 58, 60, 199, 
    198, 94, 96, 201, 114, 192, 136
  ) 
GROUP BY 
  cscart_products_categories.product_id

Query time 0.00108

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "36.36"
    },
    "grouping_operation": {
      "using_temporary_table": true,
      "using_filesort": true,
      "cost_info": {
        "sort_cost": "0.71"
      },
      "nested_loop": [
        {
          "table": {
            "table_name": "cscart_categories",
            "access_type": "ALL",
            "possible_keys": [
              "PRIMARY",
              "c_status",
              "p_category_id"
            ],
            "rows_examined_per_scan": 98,
            "rows_produced_per_join": 3,
            "filtered": "4.00",
            "cost_info": {
              "read_cost": "22.48",
              "eval_cost": "0.78",
              "prefix_cost": "23.26",
              "data_read_per_join": "13K"
            },
            "used_columns": [
              "category_id",
              "storefront_id",
              "usergroup_ids",
              "status"
            ],
            "attached_condition": "((`danishecarter_25_march`.`cscart_categories`.`storefront_id` in (0,1)) and ((`danishecarter_25_march`.`cscart_categories`.`usergroup_ids` = '') or find_in_set(0,`danishecarter_25_march`.`cscart_categories`.`usergroup_ids`) or find_in_set(1,`danishecarter_25_march`.`cscart_categories`.`usergroup_ids`)) and (`danishecarter_25_march`.`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": [
              "danishecarter_25_march.cscart_categories.category_id"
            ],
            "rows_examined_per_scan": 2,
            "rows_produced_per_join": 0,
            "filtered": "9.06",
            "index_condition": "(`danishecarter_25_march`.`cscart_products_categories`.`product_id` in (159,158,245,238,239,242,243,241,240,214,217,218,207,59,58,60,199,198,94,96,201,114,192,136))",
            "cost_info": {
              "read_cost": "10.82",
              "eval_cost": "0.14",
              "prefix_cost": "35.65",
              "data_read_per_join": "11"
            },
            "used_columns": [
              "product_id",
              "category_id",
              "link_type"
            ]
          }
        }
      ]
    }
  }
}

Result

product_id category_ids
58 188M
59 188M
60 176M
94 248M
96 248M
114 243M
136 249M
158 253M
159 253M
192 232M
198 229M
199 229M
201 230M
207 171M
214 168M
217 168M
218 168M
238 235M
239 235M
240 165M
241 165M
242 178M
243 178M
245 235M