How do I use Scrapebox for multiple sites at once?

I have a list of 100k aa backlinks.
I want to build ALL the backlinks to each website.
Do i need the automator plugin or what?

You can run several instances of scrapebox from one machine. One instance per website. That's how I would do it.
I can't post links yet, but you can find a great tutorial for setting that up by searching for: Run Unlimited Instances Of Scrapebox From The Same Machine