Any of the variables saved within the account folder -- things like your unit frames addon etc, should be the same across all toons on the account. And since these are not character specific, copy/paste from one account to the next should work just fine.

Other addons are saved within a specific characters variables folder. Many of these can be copy/pasted to other characters folders. Some don't like this, and short of trial and error, there's not an easy way to discover which are friendly to this and which are not. Even if something is "borked", you can always delete the saved variable file, and configure it manually.

I'd try to copy everything, and see what portion you can copy to set up the same. After that, you have to manually configure the rest.

Also, if you have to configure anything manually for several accounts at once. Enable your mouse broadcasting for the software, and you can at least configure everyone on your team at once, for these final stubborn steps.