You can use the Divi Theme sidebar module to add widgets to the Divi Builder. This lets you position them on the page as though they were Divi modules. here's how to do it.

  1. Go to "Appearance > Widgets" in your WordPress dashboard. There, create a new widget area using the box provided:

    Choose a name for your widget area (important – make sure there are no spaces in the name, as it doesn't seem to work otherwise). Click "Create" and refresh the page to see your new widget area. It should appear like so:

  2. Add your widget into this area, as you would the regular sidebar, by dragging across from the "Available Widgets" list on the left.
  3. Go to the edit screen for the page (or post) you wish to add the widget to. Refresh the page (saving any previous changes), so that Divi Builder can learn about the new widget area.
  4. At the appropriate place, add a new sidebar module. In the sidebar module's settings, select your Widget Area from the list:

  5. Apply any other settings you want. In particular, you may want to set "Use Border Separator" to "Yes" on the "Advanced Settings" tab. You may also want to change the admin label under "General Settings" so that your widget can be easily identified in the Divi Builder layout, like so:

  6. Finally, save the module settings and preview your page. You now should see your widget in the correct position on the page.