Anchor a keyframe? [Moon Animator]

I want to know if it is possible to anchor a keyframe.

- Context:

I’m making an animation with a sword and I want the sword to release from the arm and stay stuck on the hinge but as I have a Motor6D connecting the sword with the arm every time I move the arm the position of the sword changes.

I wanted to know if there was a way to leave it anchored or something like that.

By the way, I know that you can also put the Motor6D on the torso but it is still the same since it is also moving.

Any suggestions are welcome