A couple of suggestions to work within the system as it exists right now. Hopefully it makes your life easier.
Are these scouts who are all in a patrol? Scoutbook already does that natively. Just navigate to the patrol and select “Send Message” and it auto-selects all scouts/parents who are associated with that patrol.
If the scouts are all associated with an event, I sometimes “change” the event text to send a message, issue a Send Now reminder, then replace the original text in the event after the reminder sends.
If the scouts are “distributed” through various patrols, but affiliated in some other way (e.g. all part of a Philmont crew or members of the PLC), you can use the Scoutbook Feature Assistant Extension for Firefox and Chrome (Feature Assistant - What is it?) to create and save email groups (locally only, I believe, although they can be exported and copied to other machines). Each group can be named. I use these to send emails to our PLC, our OA arrowmen, and various other groups within the troop which don’t align with traditional patrol boundaries.
