Moving animated mask over multiple keyframes independent of layer

I created an animated mask on a background layer but the layer is larger than the canvas. There are a lot of key frames because the mask is moving with a lot of pieces. The issue is when I copy the mask to a new layer it moves in the frame due to new layer size differences. I was thinking I could just highlight all the key frames and move the mask to match, but it seems you can only move one keyframe at a time. Is there a way to move all the key frames at once on the mask layer? It's important to note I don't want to move the layer with the mask. Thank you.