Here is a script that may or may not work in current software:
http://toonboomscripts.com/2014/06/23/convert-to-2s/
CONVERT TO 2S
Leandro Mello from Brazil asked if there was a way to set a peg’s hold value to 2 automatically through scripting. If you do it manually, you have to double click each function of every peg (x, y, z, scale, etc) and set the hold value to 2. I figured it wouldn’t take long to write such a script, so I did.
Using this script will set the hold value to 2 on the selected layers/pegs ( you may change this value if you know where to find it). It will work in Harmony 10 and Animate Pro 2, but in Animate it doesn’t work on 3D pegs only on ‘separate’ pegs.
Found a post from Lilly of Toon Boom, would either of these work out?
"Well I just want to make sure that we’re talking about the same thing, because the word “tween” can mean two different things in flash/animate. You can have a shape tween (Morphing) or a motion tween (Motion keyframes). If you just have moved an object with your Transform tool, then this is simply keyframes on your timeline. You can’t convert keyframes to drawings. You can convert a morphing sequence to drawings.
If you need to get your keyframed motion on 2s, though, there are a couple of ways of doing it. You can:
1) Step function. Click on the + sign on the drawing or peg layer whose keyframes you want to step. Double-click on the function(involved in the movement to open up the Bezier Editor. Use the Step button to step the function, putting in the start value where you want to start stepping, stop value where it finishes, and a hold value of 2.
2) It’s sometimes easier just to put keyframes on every other frame (hit F6 on every other frame) then convert those keyframes to Stop-Motion keyframes by selecting them in the timeline, right-clicking, and selecting Set Stop-Motion Keyframes.
Hope this helps.
~Lilly"
[ source ] https://forums.toonboom.com/toon-boom-animate-family/support-and-troubleshooting/convert-tween-to-drawings#comment-27078