Entrance condition:

{
  "comeInWithGrappleTeleport": {
    "blockPositions": [
      [
        5,
        3
      ],
      [
        7,
        2
      ]
    ]
  }
}

Dev note: This strat has limited usefulness since you will be stuck behind the speed blocks. It could be useful if you could use a flash suit to get out; for example, the item could be an Energy Tank and you could need its refill in order to spark out (rather than sparking in). It also could be useful if the game were modified to allow retaining items after resetting.