1: The Guttenburg Embed. Good basic functionality. It’s main advantage is it free and is reliable [no plugin]. It doesn’t display immediately on mobile. You must hit the download button, then it will show up on the phone. Can be a little flaky on reload. But PC Browsers are fine.
2: embed-pdf-viewer.2.3.1 – Looks like the free guttenburg version, but doesn’t work on mobile at all.
3: pdf-embedder.4.8.2 – Looks like the free guttenburg version. But the hyperlinks don’t work on free version – wp-pdf.com branding on free version.
4: wonderplugin-pdf-embed – It basically looks like the others – WonderPlugin Lightbox function is not a free plugin. Only the premium plugin you can have a Lightbox popup. The Wonder Carousel is also not a free plugin.