Searching for "sparrow site:chessvariants.com" I found several games (mostly Shogi variants or games by Charles Gilman), but all the sparrows I found move differently than mQcK. Gilman's Sparrow is the combination piece of Rook and Arrow aka Vao or Crossbow—the diagonal counterpart of the Chinese Cannon. In notation, it is RmBcpB.
Searching for "sparrow site:chessvariants.com" I found several games (mostly Shogi variants or games by Charles Gilman), but all the sparrows I found move differently than mQcK. Gilman's Sparrow is the combination piece of Rook and Arrow aka Vao or Crossbow—the diagonal counterpart of the Chinese Cannon. In notation, it is RmBcpB.