Yes, one of the best things that happened to webflow was the ability to copy classes between projects. Okay, now I can create a “skeleton” site and copy it whenever I need it right? … not so fast my dear watson … 
depends … if you have changed some class in your new project and copy it from the skeleton will have to rename everything again to apply the new changes and possibly will lose things …
my question is … when there are conflicting classes why do not have the possibility to choose if we want to use the style of the new or old site?
imagine the case of a button.
- in my new site I have the style of .bt
- on my skeleton site I have .bt.send
- I changed the design of the .bt in my new site
- I copy from my skeleton site to the new one
- it will copy to .bt 2.send
- but i want the design of my new .bt so i need to redo the .bt 2 or rename and redo the .send
that is, nothing done my dear watson …
I know this is better than before with what we have but it is frustrating to get so close … these days I tried to copy a part of another site and I got hours renaming classes … it was worth it, but a simple option could have still avoided more work … 
I’d love this option too. For now I gotta carefully name classes on my template so it never crashes with sites I copy into 