You can change the resolution of intermediate clips in a Batch FX pipeline. However, the final clip that is output by the Batch FX pipeline must have the same resolution as the timeline.
The Batch FX Output node resizes clips to the timeline resolution. Although you cannot control the final resolution of the clip, you can use the Batch FX Output node to control other resizing options.
To access Resize from a Batch FX Output node:
The Resize menu appears. By default, it is set to resize the clip to the timeline’s default resolution.