Great, if Adidas is “in China, for China” then it can be very successful. They should invest in Chinese cotton suppliers in Xinjiang to lower their material costs as well as to regain the publics support.Adidas losses are mainly because they lost the public support of the largest economy in the world. Just making some collaborations and silently trying to restock them into unwilling local Chinese stores will not help them, it would be just a token gesture.
Instead it would be time for Adidas to earn back consumer confidence by marketing themselves as a mixture of foreign design and home grown quality materiel. Embrace and widely market Adidas's suppliers, their diversity in local design and workforce. Emphasize that it is a German - not generic western - brand, hiring local talent, local workers, using responsibly farmed and respected local material instead of cheap and dubious third world cotton.
During a period of increasing skepticism against the west caused by America's actions, Adidas, and the German government overall, can market themselves with great success if they lean into the fact that most Chinese appreciate some degree of exotic foreign work, but also want to be seen as supporting local industry and taking a consumers' stand against an aggressive west.
Even if Adidas were bastards about Xinjiang, they are better than Nike, geopolitically. Helping them, hurts Nike.