SHANGHAI, China — Joe Tsai has gone from e-commerce billionaire to NBA owner. Now he’s adding peacemaker to the list.

The Taiwanese-born, Hong Kong-based Tsai bought the Nets in August. And Tsai’s first dialogue with fans wasn’t about players or coaches, but wading into — and trying to stamp out — the firestorm caused by Rockets GM Daryl Morey’s tweet about the Hong Kong riots.

On Friday, Morey had tweeted “Fight for freedom, stand with Hong Kong.” Predictably, it didn’t go over well on the Chinese mainland. So with his Nets still in the air flying to China for this week’s preseason games, Tsai posted an open letter on Facebook trying to smooth over relations between the NBA and its biggest international market.

“I didn’t expect my first public communication with fans would be to comment on something as politically charged and grossly misunderstood as the way hundreds of millions of Chinese NBA fans feel about what just happened,” wrote Tsai.

They made it pretty clear, with several sponsors ending relations with the Rockets and multiple outlets refusing to run their games.

“The Rockets, who by far had been the favorite team in China, are now effectively shut out of the Chinese market as fans abandon their love for the team, broadcasters refuse to air their games and Chinese corporates pull sponsorships in droves,” Tsai wrote. “Fans in China are calling for an explanation — if they are not getting it from the Houston Rockets, then it is natural that they ask others associated with the NBA to express a view.”

If Chinese fans fall out of love with the Rockets, Tsai’s Nets are happy to step into the breach. While Houston has been popular thanks to Yao Ming — who as head of the Chinese Basketball Association denounced Morey’s tweet — the Nets have a golden opportunity to make headway.

The Nets face the Lakers Thursday in Shanghai and Saturday in Shenzen, with Tsai likely courtside. His ownership gives them a draw, and they’ve added Kevin Durant — who sells more shoes in China than in the U.S. — and Kyrie Irving, who also makes summer trips to China.

“There’s a very passionate fan base. That’ll probably be one of the coolest things, to just be in that environment,” Joe Harris told The Post. He played in China last month with Team USA, but expects an even more charged atmosphere vs. LeBron James & Co.

“Somebody mentioned that it’s going to be one of the most well-watched games in the history of basketball, so it’s pretty cool to take part in that,” Harris said. “There’s going to be a lot of excitement around the two teams, high-profile names; so it should be an awesome atmosphere being able to play in front of a really passionate fan base.”

Passionate, and huge. China is by far the NBA’s most vital international market. And Spencer Dinwiddie, who comes to China for production of his sneakers, has seen the country’s basketball love first-hand.

“What you notice is that there’s 400 million basketball fans in China. They have a certain love and passion for the game that’s second to none,” said Dinwiddie. “It’s going to be a lot of fun in this game. Joe Tsai, KD, Kyrie vs. LeBron, (Anthony Davis) and possibly the most famous basketball brand out there, right? It’ll be fun.”

The tickets for both games sold out in exactly one minute, and the TV viewership could be historic. The most-watched NBA tilt was Game 6 of the 1998 Finals, which got 35.89 million viewers.

But in a country where 300 million play basketball — and over twice as many watched NBA programming on TV last season — this could top those figures.

“They’re doing a great job marketing the game in different countries, and China is the second-biggest,” Wilson Chandler told The Post. He knows China well after playing here during the 2011-12 lockout. “Obviously it’s more people; it’s crazy, kind of chaotic: Every city is damn near like New York.

“There’s definitely going to be a lot of star power (this week). I think the fans are really going to come out to see that.”