TBH, a team supported by Bilibili is a tremendous move. I have never expected this.
Bilibili is one of the most popular, if not the most, video website among teenagers in China. The website formed a huge community with very rich subcultures associated with them. The company just submitted IPO on the NASDAQ in March, 2018 and this will be the best chance to expand their culture and market abroad.
While for Overwatch, this is the best chance to refocus the sight of Chinese gamers back to the game. In China, people are mostly playing LOL and PUBG, both of which are somehow experiencing recessions. On the meantime, OWL started when OW was having the hardest time in China; thus, there are few people in China actually watch OWL, especially with an extremely limited access to the live games (the viewers count on Chinese streaming websites are generally few times of the actual number, which they named after 'popularity' than 'viewers count'). Back then, there is no major streaming or video site in china have access to the game other than the one powered by NetEase. So most people will watch the game on twitch via setting up VPN. I hope the joining of Bilibili will solve this (shame on NetEase for the worst team and management of OWL).
I will say, this is a huge chance for re-popularizing Chinese OW. I highly doubt that it is Blizzard China who supported Bilibili with the team.