China’s tech stocks fell once again on Wednesday as firms backed by Tencent Holdings Ltd. came under pressure after it pared investment in the cohort for a second time in two weeks. The Hang Seng Tech Index fell 4.6%—the most since July—in a third straight day of declines, with overnight weakness in U.S. peers also weighing. The gauge closed at lowest since its inception in mid-2020 with Tencent investees Bilibili Inc., Meituan and JD.com Inc. among the biggest losers. The Chinese tech giant cut its stake in Singapore’s Sea Ltd. on Tuesday -- selling $3 billion of shares -- sparking...