Actually, that may not be eLive slowing things down. When you first install Premiere Elements or Photoshop Elements 14, it builds the media library for the Organizer -- upgrading what it can from your earlier version and then searching your hard drive for more media. It's supposed to do this in the background or when you're not working, and it can take a while. (I left my computer running overnight, and it was done before morning. But it depends on how many picture and video files you have.) If you have the preference set, it will also analyze your media to make it easier to search and manage.
Once that's done, you should find Photoshop Elements and Premiere Elements 14 running much more efficiently than previous versions.
The program checks eLive rarely. If you've got a nice lightning fast PC, you won't even see it happen.
Are you referring to slowing down of your operations within the Photoshop Elements 14 workflows on Windows 10 64 bit or are you referring to doing multitasking with other applications running on the computer when you have Photoshop Elements 14 opened and working on?
Do you have Premiere Elements 14 as well as Photoshop Elements 14? Your thread suggests just Photoshop Elements. Have you posted your thread in the Adobe Photoshop Elements Forum to take advantage of the specialized expertise there? Some how your thread got posted in the Adobe Premiere Elements Forum. However, although I have seen this type of question many times, I have yet to see the answer to how to disable eLive.
Several have asked the question that you have asked in Photoshop Elements Forum. No answers, but these discussions do bring forward reasons for wanting to disable eLive , other than slowing the computer operations.
The only sure way not to have the eLive feature (that I can think of) is to be in some parts of the world where eLive is not offered in Premiere Elements 13/13.1 and 14. In those countries, the Premiere Elements users complaint is that they do not have eLive.