Legan
Legan chess is a chess variant invented by L. Legan in 1913 (Wikipedia). It differs from standard chess by the starting position as well as by pawn movements.
Pawns move one square diagonally forward left from the player to move's perspective and similarly they capture orthogonally forward and left.
Pawns promote on squares occupied in the initial position by the opponent's king, bishops, knights, and rooks. For example, white pawns promote on squares a5–a8–d8; black pawns on e1–h1–h4. Note that the pawns that start on d1, h5, a4 and e8 cannot promote without moving toward the center of the board via capturing.