Reverse On/Off ⌃⇧R — Logic Pro keyboard command of the day

  Reverse On/Off ⌃⇧R

Toggles the Reverse parameter of an audio region on or off. When it is On the audio is played in reverse.

Logic Pro audio region parameters — Apple Support

Reverse: When selected, the region plays in reverse. The Reverse parameter is not available for regions in tracks for which Flex Time is applied.