Yes, it is genuine. Because the requirements for entering a Tmall store are very strict, in addition to company qualifications, the goods sold must have trademarks. The official flagship store you mentioned can only be applied for by Estee Lauder companies. It is the only one on Tmall that can use the words official flagship store, so it is generally genuine. Extended information

"Tmall" (English: Tmall, also known as Taobao Mall, Tmall Mall), formerly known as Taobao Mall, is a comprehensive shopping website. On the morning of January 11, 2012, Taobao Mall officially announced that it would be renamed "Tmall".

On March 29, 2012, Tmall released a new logo image. On November 11, 2012, Tmall took advantage of Singles’ Day to make a fortune, claiming to sell 10 billion in 13 hours, setting a world record. Tmall is a new B2C (Business-to-Consumer, commercial retail) created by Jack Ma’s Taobao. It integrates thousands of brands and manufacturers to provide one-stop solutions between merchants and consumers. It provides products with 100% quality guarantee, 7-day after-sales service with no reason to return, and high-quality services such as shopping points and cash back. On February 19, 2014, Alibaba Group announced that Tmall International was officially launched to directly provide domestic consumers with imported imported goods from overseas.

Reference: Baidu Encyclopedia-Tmall