I flew the T craft and taught my FAA medical examiner how to fly in it and when I got really bored one day found I had flown over 75 types of aircraft going through my log book including experimental biplanes which I certified for aerobatics for the FAA. I was lucky when aviation was not so restrictive we could do this. My FAA friend had a one of a kind mini biplane that was a blast but the only one built on some pilots garage with drawings on the floor. It was called the Bailey Bitty Bipe.
Doing slips in any airplane is easy, just push rudder one way and aileron the other. You can call it a forward slip or a side slip depending what you are using it for. We learned to do it before solo 50 years ago.
It still works today. I feel sorry for the new guys who are taught automation and didn't get to experience what I did.