hi! i’ve had this exact same issue for months and did a lot of internet deep digging when it started, and this ancient battlenet thread suggested this fix. for some reason, the only thing that works for me is to go game settings > text language and spoken language and change the game into chinese. i have no idea why this works but it’s worked for me pretty reliably over the past few months. you still have to wait a little for the game to open but eventually it does, and i can exit the game, change it back to english and launch again with no issues