Is it possible to resample the Tracker's audio output?

No, this is not possible. Tracker can't play its patterns and record audio at the same time due to its hardware limitations. It's not a matter of a firmware update. Such functionality was not really intended in a Polyend Tracker, trackers were not loopers, audio loop players nor audio recorders. Their workflow is based on short samples mostly.

One can use the "render selection" function in order to bounce steps or selections of steps from one or more tracks at the same time to a single audio file.