Minecraft 1.14 / 1.13 Motion from the player to the scoreboard?

So
2

I would like to transfer the motion of the player into the scoreboard. I have been trying for ages to find the x, y, z motion based on the objectives fx, fy, fz. Unfortunately I can't get the motion into the scoreboards.

cl

What is your previous approach?

So

I tried with execute at @a store result