How to print legs from a surround output?

No it is not possible.
If you really want to of course you can but it is a silly workaround (send signal to intermediate group channels, mute the unwanted signal and then send each now separated mono leg to each mono out).

Or you can of course re-record as interleaved and then split.
Personally I haven’t used physical re-recording in many years. I never have issues with exports (knock on wood).

Yes both of the above a workarounds for something that really should be possible