Interesting concept. I played through it a few times to get a proper feel for it. Music and aesthetic are nice.
What I found was because the position of the other character updates immediately when you press [SPACE] I typically wasn't looking at the other side which I think makes it take longer for the player to figure out how the core mechanic works, which for me at least, resulted in just pressing [SPACE] every time I couldn't progress and moving forward, brute forcing the whole game before it actually clicked what the mechanic was doing.