This one is probably too hard. Basically, when standing on the left side (in the screenshot), you have to swap UPWARDS (so that the flag is pointing downwards), fall through the tunnel, and then swap LEFT (so the flag is pointing right) just before you hit the spikes.
Thank you for playing :)
Goat it haha, so simple. I basically did a speed run to that point and almost got it first try. As I was standing on the other side, the trap door thing landed on me as I was waiting around.