How to be free to map 2 canvas with different durations

Hello, I prepare a project where my screens will move and I try to find in Millumin how to follow the mapping if the movement is not at the same speed for both.

Let's take an example, I hope to be clear enough :

One canvas moves from position 1 to 2 in 3 sec, then 2 to 3 in 3 sec, then 3 to 4 in 3 sec

The other canvas starts at the same time, moves from position 1 to 2 in 2 sec, then 2 to 3 in 4 sec, then 3 to 4 in 3 sec

It's very easy with several columns and transitions for one media.

It's very easy with timelines for 2 medias but it locks the transformation to a point of the media and for live performence it's not good.

I found a tricky way by creating one more canvas outputing in Syphon and running my movie thru this Canvas/Syphon, then build my mapping in a timeline like that I can send the transformation when I want.

But there is maybe an easier solution I missed ? Some functions in Timeline's setup ?

Thanks for your attention.

Fred