If you do need to include the full unclipped image area outside of your banner dimensions, due to the animation moving in/out of the overall banner frame area, you can optionally do this for any layer by clicking any layer's Settings icon button in the main timeline to open the layer settings, and enabling the Include full unclipped layer toggle.

This will unclip any parent frames for that layer during export and include the full layer content previously being clipped, and allow you to see that extra image area being included in animations that move the animation in/out of the banner's dimensions.

Bulk applying clipping settings. As with other layer settings, you can also apply your custom clipping setting to layers in bulk by using the bulk apply feature.

Unclipping image layers will increase file sizes. Please use this feature carefully if you need to keep your banner file sizes low. Unclipping a layer's content area will include more of the image, so this is especially important to be mindful of if your image layers are much larger in dimensions to the banner dimensions (which usually acts as the clipping size, by default).