This looks like it’s a fun semi-cooperative flow drill.

I read that baguazhang has a larger technical repertoire than that of taijiquan, but, to simplify, it seems one could start with da lu, big rollback, from taijiquan and improvise a little, covering the 8 main “energies” and go from there. The da lu two person form as I know it doesn’t include an but it could easily be added, e.g., where Yang Cheng Fu says to do shan, lightning strike.