LONDON—European shares edged higher on Wednesday and U.S. stock futures pointed to a mixed open for Wall Street, as more countries announced restrictions to reduce the spread of the Omicron variant but investors bet that the impact would be limited. Europe’s STOXX 600 was up 0.1 percent on the day 1232 GMT and the MSCI world equity index, which tracks shares in 50 countries, was up 0.2 percent. But Wall Street futures were mixed, with S&P 500 e-minis up 0.1 percent but Nasdaq futures in the red. Germany, Scotland, Ireland, Portugal, the Netherlands, and South Korea are among the countries to have reimposed lockdowns or other restrictions on activity in recent days. “Despite more reports that European governments are introducing new measures to curb the spread of COVID, market participants already seem to have made up their minds that the threat of the quick advancing Omicron variant is manageable, for …