TOKYO—European benchmarks opened mixed, with London’s FTSE 100 at nearly a two-year high, after Asian shares mostly finished lower Wednesday. France’s CAC 40 edged up 0.1 percent in early trading to 7,190.22, while Germany’s DAX slipped 0.2 percent to 15,935.45. Britain’s FTSE 100 rose 1.1 percent to 7,449.16—its highest level since February 2020, amid optimism that the omicron coronavirus variant may prove to be milder than earlier versions of the virus. U.S. shares were set to drift higher with Dow futures gaining 0.1 percent to 36,329.00. S&P 500 futures rose 0.2 percent to 4,788.25. In Asian trading, Japan’s benchmark Nikkei 225 lost 0.6 percent to finish at 28,906.88. South Korea’s Kospi slipped 0.9 percent to 2,993.29, while Australia’s S&P/ASX 200 jumped 1.2 percent to 7,509.80. Hong Kong’s Hang Seng dropped 0.8 percent to 23,086.54, and the Shanghai Composite shed 0.9 percent to 3,597.00. Although Asia has relatively few reported infection …