If what you copy out of one drawing is a complete group and nothing but the group, I can imagine a couple of approaches:
PASTEBLOCK to bring it in as a Block;
EXPLODE to separate the pieces;
GROUP and select Previous [the result of the Exploding] for the group content.
A routine could be written that would automate that.
Requiring a routine:
Set a marker variable of the last-drawn object;
PASTECLIP the stuff in;
Use (entnext) to step through and find everything newer than the marked object, and put them in a selection set;
GROUP using that selection set.
If it's a named group, putting its name into a variable first and using (vl-propagate) or (vl-bb-set) would make the name available in the target drawing to assign to the new group there. But if you're copying multiple groups, or a group and some additional objects, I can't think of a way to re-establish the grouping(s) in the target drawing.
Kent Cooper, AIA