Alkemie will premiere “Eleanor,” a new queer chamber opera by ensemble core-member Niccolo Seligmann, at the New Stage Performance Space on the Upper West Side on April 24 and 25. The semi-staged work centers on Eleanor Rykener, a gender-nonconforming person arrested in London in 1394 while presenting as a woman. The title role will be created by non-binary soprano Elisse {…}