Yes, Maps Marker Pro is compatible with WordPress 5 and the new Gutenberg editor. For general minimum requirements of Maps Marker Pro please see this FAQ.
For a future release we also plan to add a custom map block, which allows you to easily search and add shortcodes for maps (until then you need to copy and past the shortcode for a map into a block):
Step 1 – copy the shortcode, e.g. from the map edit page
Step 2 – paste the shortcode into the Gutenberg editor, which results in automatically creating a shortcode block