Tmall has an online store called Disney Fashion Flagship Store. Is the quality of that store guaranteed? Because many Tmall are fakes.

I've only heard of Disney, but I haven't heard of Guo Disney fashion. If you are careful, you can look at it first and evaluate it. Generally, Disney's products will have anti-counterfeiting labels, so you can pay attention to them when you buy them, but I think it's better to buy them at the retail counter if you look at the quality, because the texture of some materials must be touched by hand.