Most likely the mount units on qbs01 and qbs02 were generated by different versions of snapd. I suspect that qbs01 was seeded (maybe even pre-seeded) by an older version of snapd, which is why it does not have the dependency on zfs. TBH, looks like qbs02 is using an edge version of snapd?
Can you attach a similar diff for the snapd snap? Also the output of snap changes from both hosts would be useful.
Most likely the mount units on qbs01 and qbs02 were generated by different versions of snapd. I suspect that qbs01 was seeded (maybe even pre-seeded) by an older version of snapd, which is why it does not have the dependency on zfs. TBH, looks like qbs02 is using an edge version of snapd?
Can you attach a similar diff for the snapd snap? Also the output of snap changes from both hosts would be useful.