SELECT 
  cscart_june_setupproducts_categories.product_id, 
  GROUP_CONCAT(
    IF(
      cscart_june_setupproducts_categories.link_type = "M", 
      CONCAT(
        cscart_june_setupproducts_categories.category_id, 
        "M"
      ), 
      cscart_june_setupproducts_categories.category_id
    )
  ) AS category_ids, 
  product_position_source.position AS position 
FROM 
  cscart_june_setupproducts_categories 
  INNER JOIN cscart_june_setupcategories ON cscart_june_setupcategories.category_id = cscart_june_setupproducts_categories.category_id 
  AND cscart_june_setupcategories.storefront_id IN (0, 1) 
  AND (
    cscart_june_setupcategories.usergroup_ids = '' 
    OR FIND_IN_SET(
      0, cscart_june_setupcategories.usergroup_ids
    ) 
    OR FIND_IN_SET(
      1, cscart_june_setupcategories.usergroup_ids
    )
  ) 
  AND cscart_june_setupcategories.status IN ('A', 'H') 
  LEFT JOIN cscart_june_setupproducts_categories AS product_position_source ON cscart_june_setupproducts_categories.product_id = product_position_source.product_id 
  AND product_position_source.category_id = 245 
WHERE 
  cscart_june_setupproducts_categories.product_id IN (
    94, 96, 136, 90, 95, 89, 82, 84, 85, 88, 
    47, 138, 93, 87, 139, 83, 137, 248
  ) 
GROUP BY 
  cscart_june_setupproducts_categories.product_id

Query time 0.00128

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "31.76"
    },
    "grouping_operation": {
      "using_temporary_table": true,
      "using_filesort": true,
      "cost_info": {
        "sort_cost": "0.55"
      },
      "nested_loop": [
        {
          "table": {
            "table_name": "cscart_june_setupcategories",
            "access_type": "ALL",
            "possible_keys": [
              "PRIMARY",
              "c_status",
              "p_category_id"
            ],
            "rows_examined_per_scan": 84,
            "rows_produced_per_join": 3,
            "filtered": "4.00",
            "cost_info": {
              "read_cost": "19.53",
              "eval_cost": "0.67",
              "prefix_cost": "20.20",
              "data_read_per_join": "8K"
            },
            "used_columns": [
              "category_id",
              "storefront_id",
              "usergroup_ids",
              "status"
            ],
            "attached_condition": "((`vishalecarter_june_setup`.`cscart_june_setupcategories`.`storefront_id` in (0,1)) and ((`vishalecarter_june_setup`.`cscart_june_setupcategories`.`usergroup_ids` = '') or find_in_set(0,`vishalecarter_june_setup`.`cscart_june_setupcategories`.`usergroup_ids`) or find_in_set(1,`vishalecarter_june_setup`.`cscart_june_setupcategories`.`usergroup_ids`)) and (`vishalecarter_june_setup`.`cscart_june_setupcategories`.`status` in ('A','H')))"
          }
        },
        {
          "table": {
            "table_name": "cscart_june_setupproducts_categories",
            "access_type": "ref",
            "possible_keys": [
              "PRIMARY",
              "pt"
            ],
            "key": "PRIMARY",
            "used_key_parts": [
              "category_id"
            ],
            "key_length": "3",
            "ref": [
              "vishalecarter_june_setup.cscart_june_setupcategories.category_id"
            ],
            "rows_examined_per_scan": 2,
            "rows_produced_per_join": 0,
            "filtered": "8.21",
            "index_condition": "(`vishalecarter_june_setup`.`cscart_june_setupproducts_categories`.`product_id` in (94,96,136,90,95,89,82,84,85,88,47,138,93,87,139,83,137,248))",
            "cost_info": {
              "read_cost": "9.00",
              "eval_cost": "0.11",
              "prefix_cost": "30.55",
              "data_read_per_join": "8"
            },
            "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",
              "vishalecarter_june_setup.cscart_june_setupproducts_categories.product_id"
            ],
            "rows_examined_per_scan": 1,
            "rows_produced_per_join": 0,
            "filtered": "100.00",
            "cost_info": {
              "read_cost": "0.55",
              "eval_cost": "0.11",
              "prefix_cost": "31.21",
              "data_read_per_join": "8"
            },
            "used_columns": [
              "product_id",
              "category_id",
              "position"
            ]
          }
        }
      ]
    }
  }
}

Result

product_id category_ids position
47 247M
82 246M
83 246M
84 246M
85 246M
87 246M
88 247M
89 247M
90 247M
93 248M
94 248M
95 248M
96 248M
136 249M
137 249M
138 249M
139 249M
248 255,248M