At the moment, this would require creating an XForm by hand. The data collection clients are a bit ahead of XLSForm here. If you’d like to have a technical preview of what it will look like in XLSForm, please have a look here.
Could you please elaborate? Would you like to open a webform with all guidance hints opened (as is the case when you use the print button)?
It’s an unofficial and mostly undocumented Enketo-only feature to add comments to questions. Here is the technical information. Fwiw, this basic comment widget was included because of the requirement of the key Enketo sponsor (OpenClinica) that have used this widget to build a very advanced clinical data review widget on top of.