Edge in place but flipped
Step 1 / 4
D': Bottom face: turn 90°, front face goes left
The edge is already at the bottom front, but white faces front.
White cross on the bottom. The edge goes to the bottom front, between the front and white centers. D' moves the edge left, L' lifts it, D turns the cross back, F' puts the edge back in.
Step 1 of 4: D'. Bottom face: turn 90°, front face goes left