TOKYO—SoftBank Group Corp. will pause its investing in China as it waits for regulatory action against Chinese tech firms to play out, Chief Executive Masayoshi Son said on Aug. 10. “Until the situation is clearer we want to wait and see,” Son told a news conference. “In a year or two I believe new rules will create a new situation.” When the Japanese conglomerate posted record annual profit in May, executives pointed to further upside from Vision Fund investments such as Chinese ride-hailing firm Didi Global Inc. and “Uber for trucks” startup Full Truck Alliance Co Ltd. Those companies are listed in New York but Chinese regulatory action has subsequently hammered valuations, underscoring SoftBank’s China risk even as the group seeks to reduce dependence on its largest asset, a stake in Chinese e-commerce giant Alibaba Group Holding Ltd. The shift has cast a chill on SoftBank’s investing in China, which …