If you want a collection for certain photos, and that collection should contain virtual copies that you can edit and crop differently than some other version of the same photo, then select all the desired photos, then "Create Collection" and check "Include selected photos" and also check "Make new virtual copies"
Virtual copy is a very good answer for this, but there are some details to consider.
If you have manually added an image to a Collection, and then you create a virtual copy of that for a specific purpose working from inside that Collection - then that new image version will automatically inherit membership of that Collection, and appear alongside the first one there.
However if you create your virtual copy working from a different Collection or else from a folder based view then the virtual copy will not inherit that membership in the first mentioned Collection automatically.
If you don't want such a virtual copy to be in a standard Collection where it HAS appeared, you can remove / delete it from that collection without affecting its appearances elsewhere.
If you have made a Smart Collection, then where such a virtual copy meets the inclusion criteria (as it usually will, by default), then it will appear there alongside its original.
One may want to add a distinctive keyword, colour flag or whatever, or more fundamentally make use of the Virtual Copy status of an image version, in order to discriminate how it appears in Smart Collections, or to have a view filter which does that. However, there are reasons why one might want to see some Virtual Copies, but not others.
One easy and "effort free" way to discriminate only virtual copies made for the specific purpose of printing, is to create them from within the Soft Proofing mode. If you take a given image and want to fine-tune it / recrop it, go into Soft Proof selecting the output profile that is relevant. The moment you then do anything to that in Develop, you are prompted to create a "proofing (virtual) copy" which will receive those tweaks, separate from the starting version.
All VCs have a Copy Name as well as referring to a filename. A "proofing copy" automatically gets the output profile name assigned as its Copy name. This can then be used as a means of selectively finding, filtering, including or excluding... just those image versions that have been specifically tweaked under that particular profile - whether specific to a given printer and paper / specific to a given previewed colourspace.
Yes use VC’s for your different modifications. Also consider organizing your collections in Collection Sets (see image below)
It is also possible to make and name "filters" which in some way narrow down the full contents of whatever Collection, Smart Collection or Folder you may be currently looking at.
You can have some named filter presets to select for images that have a certain keyword or other atribute to express their working status (or whatever). You don't then need each Collection to have its own subcollections for those purposes... once you can achieve the same effect on-the-fly, at will, wherever.
Plus when you change anything - you haven't then got a whole lot of administrative catching-up to do..
Similar techniques can be achieved with Smart (sub) Collections which refer to collection membership - but again, that may result in a big long list since separate workflow SCs will still be needed, duplicated, per Collection. Filtering is (by contrast) completely "ad-hoc" and context neutral.