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 (
    115, 116, 117, 118, 119, 120, 121, 122, 
    123, 124, 125, 126, 127, 128, 129, 130, 
    131, 132, 133, 134, 135, 136, 137, 138
  ) 
GROUP BY 
  cscart_products_categories.product_id

Query time 0.00137

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "30.92"
    },
    "grouping_operation": {
      "using_temporary_table": true,
      "using_filesort": true,
      "cost_info": {
        "sort_cost": "0.65"
      },
      "nested_loop": [
        {
          "table": {
            "table_name": "cscart_categories",
            "access_type": "ALL",
            "possible_keys": [
              "PRIMARY",
              "c_status",
              "p_category_id"
            ],
            "rows_examined_per_scan": 83,
            "rows_produced_per_join": 3,
            "filtered": "4.00",
            "cost_info": {
              "read_cost": "19.42",
              "eval_cost": "0.66",
              "prefix_cost": "20.08",
              "data_read_per_join": "8K"
            },
            "used_columns": [
              "category_id",
              "storefront_id",
              "usergroup_ids",
              "status"
            ],
            "attached_condition": "((`satishecarter_march_003`.`cscart_categories`.`storefront_id` in (0,1)) and ((`satishecarter_march_003`.`cscart_categories`.`usergroup_ids` = '') or find_in_set(0,`satishecarter_march_003`.`cscart_categories`.`usergroup_ids`) or find_in_set(1,`satishecarter_march_003`.`cscart_categories`.`usergroup_ids`)) and (`satishecarter_march_003`.`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": [
              "satishecarter_march_003.cscart_categories.category_id"
            ],
            "rows_examined_per_scan": 2,
            "rows_produced_per_join": 0,
            "filtered": "9.74",
            "index_condition": "(`satishecarter_march_003`.`cscart_products_categories`.`product_id` in (115,116,117,118,119,120,121,122,123,124,125,126,127,128,129,130,131,132,133,134,135,136,137,138))",
            "cost_info": {
              "read_cost": "8.86",
              "eval_cost": "0.13",
              "prefix_cost": "30.27",
              "data_read_per_join": "10"
            },
            "used_columns": [
              "product_id",
              "category_id",
              "link_type"
            ]
          }
        }
      ]
    }
  }
}

Result

product_id category_ids
115 208M
116 243M
117 237M
118 244M
119 244M
120 237M
121 244M
122 208M
123 244M
124 208M
125 237M
126 251M
127 209M
128 251M
129 209M
130 251M
131 209M
132 179,182M
133 182,179M
134 182M,179
135 182M,179
136 249M
137 249M
138 249M