This is the only thing I can find.
https://www.sitepoint.com/the-ultimate-includerequire-script-for-wordpress/
The general thought I get from most other pages is to not do this.
I would probably look for another way to do this without bypassing WP. If you’re going to load all the plugins anyway you may as well load WP. But If I had to do it I would probably use get_post_meta()
to get my values instead of using the ACF functions.