HOISplitting up a 5cp map into 4 2 point sections and making it territorial control could have a similar effect provided that the round timer was 2 mins and a stalemate was a loss for the team with mid control. I don't think a plugin would be necessary and It could be interesting but potentially just less fun than normal 6s. One issue would be that whichever team begins with mid control would have an obvious advantage and I'm not sure what a good way to fix that would be other than assigning mid control randomly after a last point has been captured or just to to the team that previously lost.
so like tc_hydro