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 = 7197 
WHERE 
  cscart_products_categories.product_id IN (
    99075, 99076, 99077, 99078, 99079, 99080, 
    99081, 99082, 99083, 99084, 99085, 
    99086, 99087, 99088, 99089, 99090, 
    99091, 99092, 99093, 99094, 99095, 
    99096, 99097, 99098, 99099, 99100, 
    99101, 99102, 99103, 99104
  ) 
GROUP BY 
  cscart_products_categories.product_id

Query time 0.00112

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "30.87"
    },
    "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": 34,
            "rows_produced_per_join": 34,
            "filtered": "100.00",
            "using_index": true,
            "cost_info": {
              "read_cost": "3.67",
              "eval_cost": "3.40",
              "prefix_cost": "7.07",
              "data_read_per_join": "544"
            },
            "used_columns": [
              "product_id",
              "category_id",
              "link_type"
            ],
            "attached_condition": "(`nuie_scalesta_net`.`cscart_products_categories`.`product_id` in (99075,99076,99077,99078,99079,99080,99081,99082,99083,99084,99085,99086,99087,99088,99089,99090,99091,99092,99093,99094,99095,99096,99097,99098,99099,99100,99101,99102,99103,99104))"
          }
        },
        {
          "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": 34,
            "filtered": "100.00",
            "cost_info": {
              "read_cost": "8.50",
              "eval_cost": "3.40",
              "prefix_cost": "18.97",
              "data_read_per_join": "544"
            },
            "used_columns": [
              "product_id",
              "category_id",
              "position"
            ]
          }
        },
        {
          "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": 1,
            "filtered": "5.00",
            "cost_info": {
              "read_cost": "8.50",
              "eval_cost": "0.17",
              "prefix_cost": "30.87",
              "data_read_per_join": "4K"
            },
            "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')))"
          }
        }
      ]
    }
  }
}

Result

product_id category_ids position
99075 7255M
99076 7255M
99077 7262,7256M
99078 7262,7256M
99079 7255M
99080 7255M
99081 7262,7256M
99082 7262,7256M
99083 7255M
99084 7255M
99085 7255M
99086 7255M
99087 7255M
99088 7255M
99089 7255M
99090 7255M
99091 7255M
99092 7255M
99093 7255M
99094 7255M
99095 7255M
99096 7255M
99097 7255M
99098 7255M
99099 7255M
99100 7255M
99101 7255M
99102 7255M
99103 7255M
99104 7255M