I don’t know what your code is and with magento you may not have much ability to directly edit things (as much as you would a hand coded site from scratch), but if you add a defer attribute to the script loading tags it has the same effect as moving the js to the footer.
Second, you’ve got to look at these page speed insights with a little analysis. They are super useful but being dumb computers with no judgement they will sometimes make a big deal out of nothing. So you’ll get a failed audit over render blocking js or in my case I get them over not optimizing photos to save 4kb of bandwidth.
So if you go to your mobile phone and the page is very slow to load that is one thing. If you use an online analysis it pays to be critical at times. Last I heard googles stated ideal target is a .5 second above the fold page load, and they don’t start penalizing you until you exceed 2 seconds. So you can go to an online tool that will measure your actual load speed as opposed to what percentage of available optimizations you have in place. If your load speed is less than 2 seconds you’re pretty ok.
And yet another fix would be to inline the JavaScript. That would accomplish what you need as long as your script isn’t massive.
