It’s hard to image how the curators at the American Swedish Institute could top the revelatory, perception-transforming, aesthetically exhilarating exhibitions of recent years, from the feral folk-infused fashion of “The Weather Diaries” to Kim Simonsson’s soul-shattering sculptures of children and animals. But they have. “Shift” is the cultural institution’s theme for 2019. This means a change in focus for its exhibitions. Swedish photographer/visual artist Erik Johansson’s surrealist works usher in the year. In his worlds, fish as wide as rivers are the bedrock of inhabitable islands, roads part into ribbons of lush green fields, and kayakers navigate waterways of broken mirrors. Take a breath and plunge in.