Rolf Allard van Hagen

This plugin enables the new WordPress Gutenberg Block Editor for the Downloads post type from Easy Digital Downloads any other plugin or theme that uses a custom post type with the <code>download</code> slug.
Note: This plugin does not extend the Block Editor. If you are looking for a Downloads block to use on other pages or post, see <a href="https://wordpress.org/plugins/edd-blocks/" rel="ugc">Easy Digital Downloads – Blocks</a>.
Although EDD and all its extensions are <a href="https://docs.easydigitaldownloads.com/article/2086-wordpress-5-gutenberg-compatibility" rel="nofollow ugc">not yet guaranteed to be compatible</a> with the new editor, testing with the following plugins has not revealed any issues so far:
<ul>
<li>Easy Digital Downloads</li>
<li>EDD Software Licensing</li>
<li>EDD External Products</li>
<li>EDD Invoices</li>
<li>EDD Manual Purchases</li>
<li>EDD Recurring Payments</li>
<li>EDD Sales Recovery</li>
<li>EDD Stripe Payment Gateway</li>
</ul>
Know incompatibilities
<ul>
<li>EDD Cross-sell and Upsell</li>
</ul>
If you find any incompatibilities, please let me know on the <a href="https://wordpress.org/support/plugin/edd-block-editor" rel="ugc">Support Forum</a>.
Likewise, let me know if you find this plugin to be compatible with a plugin not mentioned here, so I can update the known list 🙂

Easy Digital Downloads – Block Editor

Enable the new WordPress block editor for Easy Digital Downloads products.

Dan Griffiths

Adds a robust third-party product system to Easy Digital Downloads. When activated, adds new fields to the Download Prices meta box allowing you to specify redirect details.
External Products is based on the extension of the same name by WebDevStudios.

Easy Digital Downloads – External Products

Was looking for exactly this: an option to add third party plugins on my own EDD shop. 

Perfect

Adds a robust third-party product system to Easy Digital Downloads

Easy Digital Downloads – Block Editor vs Easy Digital Downloads – External Products