If you work with SSIS you probably hit this wall many, many times: there's a package with zillion variables and you need to copy some / all of them to another package.
There is no copy-paste thingy in the UI for a variable so that's a dead end.
You can try to circumvent the problem by using project level parameters but that opens a separate can of worms. In the worst case scenario you will end up running a couple of packages in parallel, each overwriting some shared parameter's value. Or something like that.
Copy-paste for SSIS variables would be really desirable, right? Like, let's say, you're debugging a badly performing part of a package and you need to re-create some of its variables in a copy. There are various scenarios where you might need to do so. And how about copying SSIS vars between projects? And so on, and so forth.
So... is there a magic wand?
There is! And it is surprisingly simple (though not immediately obvious to everyone). Just open the SSIS package in the "View Code" mode (available in the right-click menu in the Solution Explorer pane) then scroll through the XML spaghetti until you find the "Variables" node, then simply copy some/all variables (each will have its own "Variable" node), finally paste them into the same "Variables" node of the target package, save and Bob's your uncle!
You are very welcome.